A Synopsis of the Present State of Knowledge of the Hardness and Abrasion Testing of Metals with Special Reference to the Work Done during the Period 1917–27,and a Bibliography

Ault E. S. “A Comparison of Modified Ball Indentation Hardness Numbers,” Mechanical Engineering, 1925, vol. 47, page 732.

Ayers J. C. “A New Method of Hardness Testing,” Proc. Amer. Soc. Testing Materials, 1918, vol. 18, part ii, page 460. The method appears to be a normal dynamic ball test.

Baker T. Russell T. F. “Note on ‘The Ball Test,'” Journal, Iron and Steel Inst., 1920, vol. ci, page 341. A series of accurate determinations on steel of the constants a and n in Meyer's Law. The relation L = bVm for ball tests is also discussed. (L = load, V = volume of indentation, b and m are constants.).

Batson R. G. “The Value of the Indentation Method in the Determination of Hardness,” Proc. I.Mech.E., 1918, vol. ii, page 463. Deals with both static and dynamic ball and cone tests. A lengthy discussion of this and other Papers is included.

Batson R. G. “Static Indentation Tests,” Proc. I.Mech.E., 1923, vol. i, page 401. Accurate experimental confirmation of law of geometrical similarity for ball tests. Compares ball and cone tests, and also suggests that the measurement of ball flattening can be used for comparative tests of very hard steels.

Baumann R. “The Hardness of Soft Metals,” Z.V.D.I., 1926, vol. 70, page 403. Suggests that impact hardness tests are more suitable for soft metals than usual static Brinell test.

Baumann R. “Hardness and Tensile Strength of Aluminium Alloys,” Z.V.D.I., 1926, vol. 70, page 1225; abstract in The Metallurgist (Supplt. to The Engineer), 1926, vol. ii, page 164.

Benedicks C. Christiansen V. “Investigations on the Herbert Pendulum Hardness Tester,” Journal, Iron and Steel Inst., 1924, vol. cx, page 219; Jernkontorets Annaler, 1924, vol. 108, page 361.

Berndt G. “Scleroscope, Ball and Scratch Hardness,” Werkstattstechnik, 1920, vol. 14, page 201.

Beuret P. “Measurement of Wear and Deformation,” Revue de Métallurgie Mémoires, 1920, vol. 18, page 157.

Bierbaum C. H. Capp J. A. Diedericks H. “Testing the Hardness of Bearings and Journals,” The Iron Age, 1920, vol. 106, page 1727. Description of the “microcharacter” scratch test.

Blenkarn G. H. “Application of the Scleroscope to Thin Brass Strip,” Journal, Inst. of Metals, 1921, vol. xxv, page 345.

Bohner H. “On the Relationship between the Brinell Hardness and Tensile Strength of Commercially Pure Aluminium and Improvable Aluminium Alloys,” Zeitschrift für Metallkunde, 1927, vol. 19, page 211; The Metallurgist (Supplt. to The Engineer), 1927, vol. 3, page 142. When care is used, it appears that an approximate indication of tensile strengths of aluminium alloys may be obtained from ball tests.

Boisthorel S. “Rapid Hardness and Energy Tests,” La Nature, 1920, vol. 2, page 230. Description of a form of dynamic ball test.

Brayton H. M. “Relation between Tensile Strength and Hardness of Steel,” The Iron Age, 1918, vol. 102, page 627.

Brinell J. A. “Resistance of Iron and Steel to Wear,” Jernkontorets Annaler, 1921, vol. 105, page 347. See page 344 of Synopsis.

Brownsdon H. W. “Brinell Hardness Numbers,” Journal, Inst. of Metals, 1923, vol. xxx, page 69. An appeal for standardization of test methods.

Brumfield R. C. “Comparison between Rockwell and Brinell Hardness,” Trans. Amer. Soc. Steel Treating, 1926, vol. 9, page 841.

Buckingham E. “The Relation of Load to Wear on Gear Teeth.” American Machinist, 1926, vol. 64, page 777.

Backwater T. V. “Hardness of Metals and Hardness Testing,” Letter to Mechanical Engineering, 1924, vol. 46, page 564.

Campbell E. D. “A Brinell Machine Attachment for Small Specimens,” Journal, Iron and Steel Inst., 1922, vol. cvi, page 193; Trans. Amer. Soc. Steel Treating, 1922, vol. 2, page 269.

Campbell H. G. White C. N. “Friction Effect in Ball Hardness Tests,” Letter to Engineering, 1925, vol. 119, page 797.

Cardullo F. E. “Hardness of Metals and Hardness Testing,” Letter to Mechanical Engineering, 1924, vol. 46, page 638. Concludes that hardness is a function of elastic modulus and limit of elasticity.

Carrington H. “Brinell Indentations,” Engineering, 1924, vol. 117, page 618. Discusses depth and diameter measurement results.

Clewell C. E. “Instruments for Hardness Tests,” American Machinist, 1919, vol. 50, page 93.

Cohade J. “Comparative Hardness Tests of Various Steel Tools at High Temperatures,” Revue Universelle des Mines, Series 7, 1924, vol. xiii, No. 1; Mechanical Engineering, 1924, vol. 46, page 214.

Collins A. L. “Scleroscope Hardness of Steel Balls,” The Iron Age, 1921, vol. 108, page 1391.

Cooke C. J. B. “Testing Hardness of Metals,” Proc. I.Mech.E., 1918, vol. i, page 331. Description of portable Boyelle-Morin apparatus for dynamic tests.

Coolidge R. H. “Hardness Tests of Metals,” Mechanical Engineering, 1921, vol. 43, page 690. Suggests the use of Prussian blue in preference to etched balls for Brinell tests on hard steels.

Coolidge R. H. “Description of the Morin Hardness Test,” Mechanical Engineering, 1921, vol. 43, page 445.

Cowdrey I. H. “Relation between the Rockwell and Brinell Hardness Scales,” Trans. Amer. Soc. Steel Treating, 1925, vol. 7, page 244. Comparative tests on over 300 metals and alloys.

Cox A. M. “The Abrasive Qualities of Plain Carbon and Alloy Steels,” Trans. Amer. Soc. Steel Treating, 1922, vol. 2, page 680. It is concluded that the ordinary tensile and Brinell tests are not reliable indications of the abrasive qualities of a material.

Craggs J. W. “Hardness Tests,” Journal, Soc. Chem. Industry, 1918, vol. 37, page 43t. Hardness tests in general are discussed, and a description of the Pellin dynamic test is given.

Crisp A. E. “Scratch Hardness Tests,” The Engineer, 1925, vol. 140, page 123.

D'Arcambal A. H. “Hardness of High Speed Steel,” Chemical and Metallurgical Engineering, 1921, vol. 25, page 1168. The conclusion is reached that scleroscope and Brinell hardness are not indications of the cutting qualities of high-speed steels.

Davis C. H. “Testing of Sheet Brass,” Proc. Amer. Soc. Testing Materials, 1917, vol. 17, part ii, page 164. Brinell and Erichsen results are given.

Davis A. L. “The Hardness of ‘Common High,’ Sheet Brass,” Trans. Amer. Soc. Steel Treating, 1923, vol. 4, page 348. A brief discussion of hardness tests as indications of quality.

Degler H. E. “A Comparison of Methods for Testing Hardness,” American Machinist, 1925, vol. 63, pages 381 and 1038.

Dews H. C. “Brinell Hardness and Machinability,” Machinery (London), 1925, vol. xxv, page 459; 1925, vol. xxvi, page 102. It is stated that Brinell hardness is not a criterion of machinability.

Dohmer P. W. “Die Brinellsche Kugeldruckprobe und ihre pracktische Anwendung bei der Werkstoffprufung in Industriebetrieben,“ (Julius Springer), Berlin, 1925. A short review of this book is given in Journal, Inst. of Metals, 1926, vol. xxxv, page 876.

Dormus A. “Note on the Wear of Rails,” Stahl und Eisen, 1926, vol. 46, page 948; abstract in The Metallurgist (Supplt. to The Engineer), 1926, vol. ii, page 135. Compares running experience with tests made in a Spindel wear machine.

Dufour P. “Apparatus for Determination of Hardness,” Revue de Métallurgie Mémoires, 1924, vol. 21, page 340. Method is a comparative simultaneous test with two balls.

Edwards C. A. “Hardness Testing,” Journal, Inst. of Metals, 1918, vol. xx, page 61. Dynamic tests on non-ferrous metals. The relation of the results to the atomic weight is also discussed.

Edwards C. A. Willis F. W. “Impact Hardness Tests,” Proc. I.Mech.E., 1918, vol. i, page 335. Describes a dynamic method of test, using a 10 mm. ball; the impressions are measured after test.

Edwards C. A. Austin C. R. “A Contribution to the Study of Hardness,” Journal, Iron and Steel Inst., 1923, vol. cvii, page 323. Deals largely with ball rebound tests.

Esnault-Pelterie R. “Apparatus for Measurement of Hertzian Hardness,” Revue de Métallurgie Mémoires, 1926, vol. 23, page 553; also in English, The Engineer, 1928, vol. 146, pages 180, 195 et seq. Describes two methods of determining Hertzian hardness of hardened steel balls.

Fogler M. F. Quinn E. J. “Scratch and Brinell Hardness of Severely Cold-Rolled Metals,” Trans. Amer. Inst. Min. and Metal. Engrs., 1925, vol. 71, page 889. The results indicate that a reversal of hardness as found by Rawdon and Mutchler is not universally true.

de. Forrest A. V. “A Simple Type of Brinell Testing Machine for 500 kg. Load,” Proc. Amer. Soc. Testing Materials, 1918, vol. 18, part ii, page 449.

de. Forrest A. V. “Magnetic Indications of Hardness and Brittleness,” Trans. Amer. Soc. Steel Treating, 1923, vol. 4, page 342.

Foss F. E. Brumfield R. C. “Measurements of the Shapes of Brinell Ball Indentations,” Proc. Amer. Soc. Testing Materials, 1922, vol. 22, part ii, page 312. A series of accurate measurements of actual shapes of ball indentations.

French H. J. “Wear Testing of Metals,” Proc. Amer. Soc. Testing Materials, 1927, vol. 27, part ii, page 212. The report is a brief summary of the present status of wear testing of metals, and includes results of experimental work to show that reproducible results and information consistent with practical experience can be secured in the laboratory.

French H. J. Herschmann H. K. “Wear of Steels with Particular Reference to Plug Gauges,” Trans. Amer. Soc. Steel Treating, 1926, vol. 10, page 683. See page 343 of Synopsis.

French H. J. Herschmann H. K. “Recent Experiments Relating to the Wear of Plug Gauges,” Trans. Amer. Soc. Steel Treating, 1927, vol. 12, page 921. See page 343 of Synopsis.

Genders R. “The Scleroscope Test; a New Form of Magnifier Hammer,” Journal, Inst. of Metals, 1923, vol. xxix, page 445.

German H. M. “Testing of Steel for Hardness,” Trans. Amer. Soc. Steel Treating, 1923, vol. 4, page 329. Classifies the types of hardness testing machines.

German H. M. “Standardizing the Brinell Test,” Trans. Amer. Soc. Steel Treating, 1927, vol. 11, page 54. The author points out the defects in different types of Brinell machines and describes a new design which will overcome certain defects and eliminate the personal factor.

Goodale S. L. Banks R. M. “Brinell Tests for Thin Brass Sheet,” Proc. Amer. Soc. Testing Materials, 1919, vol. 19, part ii, page 757. Describes a small ball Brinell machine, frac1o16-inch diameter ball and load of 15 kg.

Greaves R. H. Jones J. A. “The Ratio of the Tensile Strength of Steel to the Brinell Hardness Number,” Journal, Iron and Steel Inst., 1926, vol. cxiii, page 335. Gives a valuable statistical examination of the ratio for over 1,100 tests. The results of other workers are also fully-considered and discussed.

Guillery R. “Hardness Tests.” Comptes Rendus de l'Académie des Sciences, 1917, vol. 165, page 468. Describes a machine by means of which Brinell tests may be made very rapidly.

Guillery R. “A Study of the Ball Hardness Test,” Mémoires Soc. Ing. Civils, 1920, page 591; Revue de Métallurgie Mémoires, 1921, vol. 18, page 101. Suggests a modification of the Brinell test whereby the influence of the time of loading may be eliminated.

Guillery R. “Impact Hardness Testers,” La Nature 1920, vol. 2; Technical Review, 1921, vol. 8, page 139. A description of a dynamic ball test apparatus is given; the release of a compressed spring causes the impact.

Guillet L. “Wearing Properties of Anti-Friction Metals in contact with Steel,” Revue de Métallurgie Mémoires, 1922, vol. 19, page 117.

Guillet L. Galibourg J. “Results of Tests with the Herbert Pendulum,” Revue de Métallurgie Mémoires, 1925, vol. 22, page 238. Concludes that the pendulum is of use in certain cases where other methods fail.

Hadfield R. A. Sir Main S. A. “Brinell and Scratch Tests for Steel,” Proc. I.Mech.E., 1919, vol. ii, page 581. Brinell hardness found to be approximately proportional to the inverse cube of scratch width.

Haigh B. P. “Prism Hardness,” Proc. I.Mech.E., 1920, vol. ii, page 891. See page 331 of Synopsis. An interesting discussion of the meaning of hardness is also given in the Paper.

Hankins G. A. “Scratch Hardness Tests,” Proc. I.Mech.E., 1923, vol. i, page 423; Engineering, 1923, vol. 115, page 537. A detailed experimental examination of the diamond scratch test on steels, when the scratches are caused by flow of the metal.

Hankins G. A. “The Effects of Adhesion between the Indenting Tool and the Material in Ball and Cone Hardness Tests,” Proc. I.Mech.E., 1925, vol. i, page 611; Engineering, 1925, vol. 119, page 556. Shows that adhesion or friction occurs in static indentation tests, and that when allowance is made for it, ball and cone tests agree within certain defined limits.

Hankins G. A. “Diamond Cone Indentation Hardness Tests,” Proc. I.Mech.E., 1926, vol. ii, page 823. An extensive examination of diamond cone indentation tests; suggests that friction is low (μ = 0·1) on all hard steels. Suggests that the 120° cone test is likely to be a satisfactory form of diamond indenter for static tests.

Herbert E. G. “Some Recent Developments in Hardness Testing,” The Engineer, 1923, vol. 135, page 686. See page 331 of Synopsis. Initial description of the pendulum tester.

Herbert E. G. “Influence of Temperature on the Work Hardening of Metals,” The Engineer, 1924, vol. 137, pages 248 and 356.

Herbert E. G. “The Measurement of Cutting Temperatures,” Proc. I.Mech.E., 1926, vol. i, page 289.

Herbert E. G. “Work-Hardening Properties of Metals,” Trans. Amer. Soc. Mech. E., 1926, vol. 48, page 705; The Engineer, 1927, vol. 143, pages 138, 156, and 180. See page 331 of Synopsis.

Herbert E. G. “The Work Hardening of Steel by Abrasion,” Journal, Iron and Steel Inst., 1927, vol. cxvi, page 265.

Herbert E. G. Report on Cutting Temperatures. Proc. I.Mech.E., 1927, vol. ii, page 863.

Hencky H. “Certain Statically Determinate Cases of Equilibrium in Plastic Bodies,” Zeitschrift für angewandte Mathematik und Mechanik, 1923, vol. 3, page 241.

Hitchcock F. P. “A Universal and Practical Machine for Determining the Resistance of Metals to Wear under the Various Kinds of Friction Encountered in Practice,” Testing (New York), 1924, vol. 1, page 147. A description of the Amsler wear-testing machine.

Hollnagel H. P. “Significance of Hardness Testing,” Trans. Amer. Soc. Steel Treating, 1923, vol. 3, page 480. Draws attention to the diversity of opinions regarding the definition of hardness.

Hollnagel H. P. “Hardness Numbers and their Relation,” The Iron Age, 1924, vol. 114, page 1404; 1925, vol. 115, page 770. Discusses the physical meaning of hardness and concludes that hardness numbers should be expressed in terms of work per unit volume per unit strain.

Hollnagel H. P. “Stress-Strain Curves and Physical Properties of Metals with Particular Reference to Hardness,” Trans. Amer. Soc. Steel Treating, 1926, vol. 10, page 87. A thoughtful contribution in which it is shown that rational ideas on hardness can be obtained from stress-strain curves. No experimental results are given.

Holz H. A. “Brinell's Researches on Resistance to Wear,” Testing (New York), 1924, vol. 1, page 104. Lengthy account in English of Brinell's experiments, Reference 16 of this Bibliography.

Holz H. A. “Elastic Column Dynamometer for Hardness Testing,” Chemical and, Metallurgical Engineering, 1923, vol. 28, page 269.

Holz H. A. “The Logical Course of Development of Additional Apparatus for Investigating the Hardness of Metal Products in Works Practice,” Testing (New York), 1924, vol. 1, page 247.

Honda K. “Mechanical Theory of Metals,” Science Reports. Tohoku Imperial University, 1917, vol. 6, page 95. The theory may be briefly expressed as follows. For a given substance having a definite molecular force its hardness increases with the fineness and the strained state of the structure, and for the same structure and same degree of strain, the hardness of a substance increases with the strength of its molecular force.

Honda K. Takahasi K. “On the Indentation Hardness of Metals,” Journal, Iron and Steel Inst., 1924, vol. cix, page 323. Suggests that ball tests should be expressed in a particular manner from depth measurements.

Honda K. Yamada R. “Some Experiments on the Abrasion of Metals,” Journal, Inst. of Metals, 1925, vol. i, page 49. Wear tests in which the frictional energy absorbed was also determined.

Honda K. Takahasi K. “A Further Investigation of the Indentation Hardness of Metals,” Journal, Iron and Steel Inst., 1927, vol. cxv, page 717. A continuation of the previous work of these authors, Reference 84.

Hoyt S. L. “The Ball Indentation Hardness Test,” Trans. Amor. Soc. Steel Treating, 1924, vol. 6, page 396; The Metallurgist (Supplt. to The Engineer), 1925, vol. i, page 11. A lengthy discussion of Meyer's analysis of the ball test and its application.

Hoyt S. L. Schermerhorn T. R. “The Hardness of Cold-Rolled Copper,” Journal, Inst. of Metals, 1926, vol. xxxv, page 231.

Hultgren A. “Improvements in the Brinell Test on Hardened Steel, including a New Method of Producing Hard Steel Balls,” Journal, Iron and Steel Inst., 1924, vol. cx, page 183. Describes the preparation of, and various tests on work-hardened steel balls. Shows they are more suitable than ordinary steel balls for Brinell tests on hard steels.

Hurst J. E. “Wearing Properties of Cast Iron,” Iron and Steel Institute, Carnegie Scholarship Memoirs, 1918, vol. ix, page 59.

Innes J. “Measurement of High Degrees of Hardness,” Proc. I.Mech.E., 1920, vol. ii, page 915. The definition and measurement of hardness are discussed, mainly with reference to Hertzian hardness.

Irion E. “Hardness Testing Machines,” Z.V.D.I., 1921, vol. 65, page 315. Describes various ball hardness testing machines manufactured by Dusseldorfer Maschinenbau A. G.

Jannin L. “A New Method of Testing the Wearing Properties of Metals,” Revue de Metallurgie Mémoires, 1922, vol. 19, page 109.

Jones J. L. Marshall C. H. “A New Method of Calibrating Brinell Hardness Testing Machines,” Proc. Amer. Soc. Testing Materials, 1920, vol. 20, part ii, page 392.

Jones R. L. “Increasing the Speed of the Scleroscope,” American Machinist, 1924, vol. 61, page 783.

Keller J. O. “Comparison of Herbert Pendulum Tester with other Hardness Testers,” Mechanical Engineering, 1924, vol. 46, page 818; 1925, vol. 47, page 282.

Kiyosi I. “Hardness of Metals as affected by Temperature,” Science Reports, Tohoku Imperial University, 1923, vol. 12, page 137.

Kokado S. “Hardness and Hardness Measurement,” Technology Reports of the Tohoku Imperial University, 1927, vol. 6, page 201.

Korber F. Simonsen I. B. “Dynamic Hardness Testing by the Differential Method,” Mitteilungen aus dem Kaiser-Wilhelm Institut für Eisenforschung, 1922, vol. 4, page 61.

Kugler C. “Testing the Hardness of Metals,” American Machinist, 1925, vol. 63, page 823. Description of a cheap workshop method of making ball tests.

Lake E. F. “Hardness Testing and Toughness,” The Iron Age, 1922, vol. 109, page 913. Forging and Heat-Treating, 1922, vol. 8, page 313. Discusses the limitations of various hardness tests, and says that a commercial test of toughness is required.

Le Chatelier H. Le Génie Civil, 1917, vol. 70, page 95. Comptes Rendus de l'Académie des Sciences, 1917, vol. 164, page 205. Among other matters points out the need for an accurate hardness test for hard steels.

Le Chatelier H. Bogitch B. “Brinell Tests,” Comptes Rendus de l'Académie des Sciences, 1918, vol. 166, page 840. Describes an application of the ball test to brittle materials.

Lehmann O. H. “The Wear of Cast Iron under Sliding Friction,” Giesserei Zeitung, 1926, vol. 23, pages 597, 623, and 654; Foundry Trade Journal, 1927, vol. 35, page 173. See page 342 of Synopsis.

Leslie R. M. “Definition of Hardness,” Engineering, 1918, vol. 106, page 153.

Le Rolland P. “The Measurement of Hardness by the Pendulum,” Revue de Métallurgie Mémoires, 1926, vol. 23, page 567. Describes a new form of pendulum hardness test using a 5 mm. diameter glass ball.

Lieber P. “The Duration of Loading in Hardness Tests on Soft Metals,” Zeitschrift für Metallkunde, 1924, vol. 16, page 128. Finds that a time of loading of at least three minutes is necessary on soft material such as bearing metals.

Ludwik P. “Hardness of Alloys,” Z.V.D.I., 1917, vol. 61, page 549; Engineering, 1917, vol. 104, page 444. Gives the results of cone hardness tests on a large number of the most important alloys. The theoretical side of the subject is also discussed with reference to hardness of solid solutions.

Ludwik P. “Change of Hardness with Temperature,” Zeitschrift für Physikalische Chemie, 1916, vol. 91, page 232. Curves are given for a number of non-ferrous metals.

Ludwik P. “Cohesion, Hardness and Toughness,” Zeitschrift für Metallkunde, 1922, vol. 14, page 101. The definitions of the properties are discussed, and the relations between them are examined at some length.

Mailander R. “Duration of Loading and Ball Hardness.” Kruppsche Monatschefte, 1924, vol. 5, page 209. Concludes that results are correct within 3 per cent when the duration of loading is 10 seconds for steels, 20 seconds for iron, and 2 minutes or more for softer metals.

Mailander R. “Hardness Testing of Hardened Steels,” Stahl und Eisen, 1925, vol. 45, page 1769; Kruppsche Monatschefte, 1925, vol. 6, page 204. Concludes that normal steel balls are unsatisfactory for Brinell tests on materials over 450 Brinell number. Also finds that n in Meyer's equation P = adⁿ is dependent on the ball when determined for hard steels.

Mallock A. “Stresses in Hardness Tests,” Nature, 1926, vol. 117, page 117; 1927, vol. 119, page 276. Hardness can be determined by pressing a cone of the material against a hard surface. Also says that hardness is unrelated, apparently, either to density, atomic weight or position in the periodic classification.

McCance A. “Stress Lines in Steel after Permanent Deformation,” Trans. Inst. Engrs. and Shipbdrs. in Scotland, 1919, vol. lxii, page 252.

Meyer H. Nehl F. “Wear Tests of Iron and Steel under Rolling Friction without Lubrication,” Stahl und Eisen, 1924, vol. 44, page 457. See page 340 of Synopsis.

Moore H. “A Small Ball Hardness Testing Machine,” Proc. I.Mech.E., 1921, vol. i, page 51. A description of the “Baby” Brinell machine.

Moore H. “The Ball Hardness Test,” Metal Industry, 1922, vol. 20, page 510.

Moore H. “The Effect of Progressive Cold Rolling on the Brinell Hardness of Copper,” Journal, Inst. of Metals, 1924, vol. xxxii, page 407. It is stated that convincing evidence of any marked softening occurring generally in metals and alloys when cold rolled is still lacking.

Moore R. R. “Relationships between Rockwell, Brinell and Scleroscope Numbers,” Trans. Amer. Soc. Steel Treating, 1927, vol. 12, page 968.

Moreau G. “The Hardness of Bodies under Shock,” Journal de Physique, 1921, vol. vi, ii, page 329. The duration of impact in a dynamic hardness test was determined by electrical methods.

Moser M. “Observations on the Brinell Hardness Test,” Stahl und Eisen, 1925, vol. 45, page 343. Shows that the Brinell test can only be accurate when the crystallites of the material are small in comparison with the size of the indentation.

Mouillac R. “The Herbert Pendulum for Hardness Tests,” Revue de Métallurgie Mémoires, 1925, vol. 22, page 223. Gives the results of an investigation of the pendulum test.

Nicolau P. “Investigation of the Jannin Wear Test and its Application to Anti-friction Metals,” Revue, de Métallurgie Mémoires, 1924, vol. 21, page 347.

Nicolau P. “Remarks on the Use of the Herbert Pendulum,” Revue de Métallurgie Mémoires, 1925, vol. 22, page 245.

Norbury A. L. “The Hardness of Annealed Copper,” Journal, Inst. of Metals, 1923, vol. xxix, page 407.

Norbury A. L. “The Hardness of Copper Solid Solutions,” Journal, Inst. of Metals, 1923, vol. xxix, page 423.

Norbury A. L. “Experiments on the Hardness of Lead,” Trans. Faraday Soc., 1923, vol. xix, page 140.

Norbury A. L. Samuel T. “Experiments on the Brinell-Tensile Relationship,” Journal, Iron and Steel Inst., 1924, vol. cix, page 479. Comparison of values of a and n in Meyer's Law with tensile strength.

O'Neill H. “The Measurement of Hardness of Metals,” Mechanical World, 1920, vol. 68, page 383. (Paper to the Sheffield Metallurgical Society.) A general description and discussion of indentation hardness tests.

O'Neill H. “Ball Hardness and Scleroscope Hardness,” Nature, 1923, vol. 111, page 430. Suggests that the “ultimate hardness” is given when the ball is embedded up to its centre.

O'Neill H. “Variation of Brinell Hardness with Testing Load,” Journal, Iron and Steel Inst., 1923, vol. cvii, page 343. Extensive data on this feature of ball tests are given.

O'Neill H. “Hardness Tests on Crystals of Aluminium,” Journal, Inst. of Metals, 1923, vol. xxx, page 299.

O'Neill H. “Hardness and its Relation to Working and Machining Properties of Metals,” Iron and Steel Institute, Carnegie Scholarship Memoirs, 1926, vol. xvi, page 233; 1928, vol. xvii, page 109. A series of liaison experiments with reference to various features of static indentation tests.

O'Neill H. Thompson F. C. “A Curious Feature in the Hardness of Metals,” Nature, 1922, vol. 110, page 773.

Page A. R. “Testing Materials for Hardness,” American Machinist (European edition), 1926, vol. 65, page 66e. The Brinell, diamond pyramid, and Rockwell tests are described.

Petrenko S. N. “The Mechanical Meaning of Hardness,” Mechanical Engineering, 1924, vol. 46, page 926.

Petrenko S. N. “Elastic Ring for Verification of Brinell Hardness Testing Machines,” Trans. Amer. Soc. Steel Treating, 1926, vol. 9, page 420. The apparatus described was developed at the Bureau of Standards. Recommendations, based on experience at the Bureau of Standards, are given for the best procedure in Brinell testing.

Petrenko S. N. “Relationship between Rockwell and Brinell numbers,” Technologic Papers, Bureau of Standards, U.S.A., 1927, vol. 22, No. 334. An extensive comparison of results.

Picarelli A. “Influence of Thickness of Test-Piece in Hardness Tests,” Metallurgia Italiana, 1918, vol. 10, page 259.

Plaut . “Scientific and Technical Measurement of Hardness,” Zeitschrift für Metallkunde, 1923, vol. 15, page 328. Discusses the meaning of hardness.

Pomp A. Schweinits H. “The Herbert Pendulum Testing Machine and its Adaptability for Testing Industrial Materials,” Mitteilungen aus dem Kaiser-Wilhelm Institut für Eisenforschung, 1926, vol. 6, page 79. A rather critical examination of the pendulum tester.

Portevin A. “Hardness of Worked Copper and Brass,” Revue Ac Metallurgie Mémoires, 1919, vol. 16, page 235.

Portevin A. “Use of the Brinell Test for Testing the Tensile Strength of Castings,“ Franco-Belgian Testing Association, Oct. 1921; Le Génie Civil, 1921, vol. 79, page 402. Suggests that the tensile strength of castings can be obtained from the Brinell test.

Prandtl L. “On the Resistance to Penetration of Plastic Materials of Construction and the Strength of Cutting Edges,” Zeitschrift für angewandte Mathematik und Mechanik, 1921, vol. 1, page 15.

Prandtl L. “The Distribution of Stresses in Plastic Bodies,“ Proc. International Congress for Applied Mathematics, Delft, 1924, page 43.

Primrose H. S. Primrose J. “Testing Appliances,” Proc. I.Mech.E., 1920, vol. ii, page 933. Mainly description of standardizing boxes and depth-measuring appliances for hardness tests.

Quick G. W. Jordan L. “Iron Carbon Vanadium Alloy for Brinell Balls,” Trans. Amer. Soc. Steel Treating, 1927, vol. 12, page 3. Report on investigation of hard balls carried out at the Bureau of Standards.

Rawdon H. S. Report of Sub-Committee on Micro (Scratch) Hardness, Proc. Amer. Soc. Testing Materials, 1925, vol. 25, part i, page 442; 1926, vol. 26, part i, page 572. Consideration of results given by Bierbaum's scratch test. It is concluded that the test is not very accurate, nor is it suitable for measuring work-hardness of cold-drawn metals, but is useful for showing variations of constituents of heterogeneous materials. A complete bibliography of scratch hardness tests is given.

Rawdon H. S. Mutchler W. H. “Effect of Cold-Working on Scratch and Brinell Hardness,” Trans. Amer. Inst. Min. and Metal. Engrs., 1924, vol. 70, page 342. Finds that the hardness increases to a maximum and then diminishes.

Rawdon H. S. Jimeno-Gil E. “Relation between Grain Size and Brinell Hardness of Annealed Carbon Steels,” Scientific Papers, Bureau of Standards, U.S.A., 1920, vol. 16, No. 397. It is concluded that grain size is a factor of minor importance in the determination of Brinell numbers of carbon steels.

Redenz H. “Wear Tests on Chromium Steel for Ball-Bearings,” Stahl und Eisen, 1924, vol. 44, page 1703.

Reid C. O. “Wear Tests,” Testing (New York), 1924, vol. 1, page 93. General review of results given by wear tests.

Robin F. “Hardness Measurement,” Société d'Encouragement pour l'Industrie Nationale, Bulletin No. 127, 1917, page 233. Describes a particular form of indentation test in which a circular knife-edge cutter is used to produce the indentation.

Rockwell S. P. “The Testing of Metals for Hardness,” Trans. Amor. Soc. Steel Treating, 1922, vol. 2, page 1013. A comparison of Brinell, Rockwell and scleroscope results.

Rossi P. “Brinell Hardness,” Metallurgia Italiana, 1919, vol. 11, page 436. A discussion of depth measurement results in ball tests.

Rossi P. “Thermal and Mechanical Hardening as Revealed by the Indentation Method,” Il Nuovo Cimento, 1924, vol. 1, page 243. Includes a discussion of Meyer's Law and the effect of work-hardening.

Rudolph O. C. “An Improved Microscope for Ball Tests,” Testing (New York), 1924, vol. 1, page 45.

Sachs G. “Contribution to the Hardness Problem,” Naturwiss, 1926, vol. 14, page 1219. Indentation tests on prismatic compounds of iron and copper are in accordance with the elastic theoretical distribution of stress.

Sachs G. “Plasticity Problems in Metals” (Symposium), Trans. Faraday Soc., 1928, vol. xxiv, page 84.

Sauerwald F. Knehans K. “Concerning the Dependence of the Hardness of Metals on Temperature,” Zeitschrift für Metallkunde, 1924, vol. 16, page 315. Experimental results are given for iron and a number of non-ferrous metals.

Sauveur A. “The Durometer, an Instrument for Testing Hardness,” Trans. Amer. Soc. Steel Treating, 1926, vol. 9, page 929. A form of ball rebound test.

Schuz E. “Relation between Tensile Strength and Hardness of Cast Iron,” Stahl und Eisen, 1923, vol. 43, page 720.

v. Schwarz M. “The Graven Ball Hammer Test,” Zeitschrift für Metallkunde, 1921, vol. 13, page 429. Describes a practical form of dynamic ball test.

Shires G. A. “Some Practical Aspects of the Scratch Hardness Test,” Proc. I.Mech.E., 1925, vol. 1, page 647. Shows that the diamond scratch test is limited by the accuracy required in measurements of scratch widths.

Shore A. F. “Relation between Ball Hardness and Scleroscope Hardness.” Journal, Iron and Steel Inst., 1918, vol. xcviii, page 59. An extensive study of the relation between scleroscope and ball indentation tests.

Shore A. F. “The Standardization of Methods of Applying the Scleroscope,” Journal, Society of Automotive Engineers, 1923, vol. 13, page 409.

Slater I. Turner T. H. “The Hardness of Carbon Steels at High Temperatures,” Journal, Iron and Steel Inst., 1926, vol. cxiii, page 295.

Smith R. L. Sandland G. “An Accurate Method of Determining the Hardness of Metals with Particular Reference to those of a High Degree of Hardness,” Proc. I.Mech.E., 1922, vol. i, page 623. Describes static indentation tests with uncut diamond indenters.

Smith R. L. Sandland G. “Notes on the Use of a Diamond Pyramid for Hardness Testing,” Journal, Iron and Steel Inst., 1925, vol. cxi, page 285. Results of tests carried out in the Vickers diamond hardness testing machine.

Spalding S. C. “Comparison of Brinell and Rockwell Tests on Hardened High Speed Steel,” Trans. Amer. Soc. Steel Treating, 1924, vol. 6, page 499.

Spindel M. “The Resistance to Wear of Railway Material,” Z.V.D.I., 1926, vol. 70, page 415; The Metallurgist (Supplt. to The Engineer), 1926, vol. ii, page 83. See page 341 of Synopsis.

Stadeler A. “Dependence of Wear upon the Microstructure,” Stahl und Eisen, 1925, vol. 45, page 1195. It is concluded that steel in a fine-grained condition obtained by treatment resists wear much better than the same steel in the normal state as rolled.

Susuki M. “On the Abrasion of Carbon Steels,” Journal, Soc. Mech.E. (Tokyo), 1927, vol. xxx, page 559.

Thompson F. C. “Some Recent Advances in the Measurement of Hardness of Metals,” Journal, Soc. of Chem. Industry, 1919, vol. 38, page 241r.

Tritton F. S. “The Use of the Scleroscope on Light Specimens of Metals,” Journal, Inst. of Metals, 1921, vol. xxvi, page 261.

Turner T. “Hardness and Hardening,” Journal, Inst. of Metals, 1917, vol. xviii, page 87. An interesting general discussion of the nature and meaning of hardness.

Tuckerman L. B. “Hardness and Hardness Testing,” Mechanical Engineering, 1925, vol. 47, page 51. Hardness tests as embodied in specifications are discussed.

Unwin W. C. “The Ludwik Hardness Test,” Proc. I.Mech.E., 1918, vol. ii, page 485. Traces the relationship between ball and cone tests.

Unwin W. C. “Definition of Hardness,” Engineering, 1918, vol. 105, page 535, see also pages 587, 632, 691, 734.

Unwin W. C. “The Brinell and Scratch Test of Hardness,” Engineering, 1919, vol. 108, page 669, see also pages 728, 749, 797.

Waizenegger F. “Contribution to the Knowledge of Hardness,” Z.V.D.I., 1921, vol. 65, page 824. A general discussion of ball tests and of Meyer's Law. The use of a maximum ball hardness number, derived from Meyer's Law is suggested.

Whittemore H. L. “The Need for Cheaper Hardness Tests,” Mechanical Engineering, 1925, vol. 47, page 223.

Williams S. R. “Hardness Testing of Steel Balls by Magnetic Methods,” Trans. Amer. Soc. Steel Treating, 1924, vol. 5, page 479; 1927, vol. 11, page 677.

Wild L. W. “Magnetic Hardness of Ferrous Metals,” Trans. Faraday Soc., 1920, vol. xv, part 3, page 1.

Wust F. Bardenheuer P. “Hardness Testing by the Loaded Drop Ball Method,” Mitteilungen aus dem Kaiser-Wilhelm Institut für Eisenforschung, 1920, vol. 1, page 1. Confirms the work of previous investigators as to the laws governing dynamic ball tests. Miscellaneous. Machines.—.

“ Scimato Brinell Hardness Testing Machine,” Metallurgical and Chemical Engineering, 1916, vol. 14, page 58.

“Waldo Hardness Testing Apparatus,” Metallurgical and Chemical Engineering, 1917, vol. 16, page 710.

“Brinell Machine for High Temperature Testing,” Engineering, 1920, vol. 109, page 157.

“Brinell Testing Machine for Large Forgings,” Engineering, 1921, vol. 111, page 680.

“Riehle Combination Brinell and Scleroscope Hardness Testing Machine,” American Machinist, 1921, vol. 55, page 363.

“The Brinell Test, Two New Machines,” Machinery (London), 1921, vol. 18, page 459.

“Amsler 5000 kg. Hardness Tester,” American Machinist (European edition), 1923, vol. 58, page 69e.

“Hardness Testers,” Mechanical Engineering, 1925, vol. 17, page 282.

“Ball Hardness Testing Machine with Grinding Machine,” American Machinist (European edition), 1925, vol. 63, page 217e.

“Rudge-Whitworth Auto-Punch for Hardness Tests,” American Machinist, 1922, vol. 56, page 118.

“Vickers Diamond Hardness Testing Machine,” Engineering, 1924, vol. 117, page 518; American Machinist (European edition), 1925, vol. 62, page 73e.

“The Firth Hardometer,” Machinery (London), 1926, vol. 28, page 51; Mechanical World, 1926, vol. 79, page 3.

“Rockwell Hardness Tester,” Machinery (London), 1923, vol. 21, page 534.

“Rockwell Hardness Tester for Large Pieces,” The Iron Age, 1925, vol. 116, page 81.

“Herbert Pendulum Hardness Tester,” Machinery (London), 1923, vol. 22, page 76.

“Recording Scleroscope and Pneumatic Release Pedal,” Engineering, 1923, vol. 115, page 185.

“Amsler Abrasion Testing Machine,” American Machinist, 1924, vol. 60, page 128e. Hardness Testing.—.

“Table of Brinell Hardness Numbers,“ British Engineering Standards Association, Report No. 240, 1926.

“Brinell Hardness Numbers,“ Bureau of Standards, U.S.A. 1924, Miscellaneous Publication No. 62. Standard tables for 10 mm. ball tests, 500 kg. and 3,000 kg. loads.

“Bibliography of Hardness Testing” (up to 1923), Trans. Amer. Soc. Steel Treating, 1923, vol. 4, page 507.

“Hardness Testing of Metals,” Report of Committee of Engineering Division, National Research Council (U.S.A.), Mechanical Engineering, 1921, vol. 43, page 445. Describes the etched ball method, the Morin hardness testing apparatus, and the Brinell meter.

“Hardness of Metals and Hardness Testing,” Mechanical Engineering, 1924, vol. 46, page 360 and 502; 1925, vol. 47, pages 282 and 363. Further report of the above committee. Discusses various methods of hardness testing.

“Tentative Methods of Brinell Hardness Testing of Metallic Materials,” Proc. Amer. Soc. Testing Materials, 1924, vol. 24, part i, pages 701 and 1099; 1925, vol. 24, part i, page 872. Tentative standards are suggested.

“New Process for Testing the Resistance to Wear of Railway Material,” Z.V.D.I., 1922, vol. 66, page 1071. Refers to tests in the Spindel machine.

“Brinell Hardness and Tensile Strength of Cast Iron,“ British Cast Iron Research Association, Bulletin No. 10, 1925. Concludes that the Brinell test is unsuitable for estimating the tensile strength of cast iron.

“The Quality of Hardness,” Engineering, 1923, vol. 115, page 527.

“Hardness and Solid Viscosity of Metals,” The Engineer, 1923, vol. 135, page 449.

“The Herbert Cloudburst Hardness Testing Machine,” Engineering, 1928, vol. 126, page 28. Addenda—.

Ham C. W. Huckert J. W. “An Investigation of the Efficiency and Durability of Spur Gears,“ Univ. of Illinois, Engineering Experiment Station, Bulletin No. 149, 1925.

Hargreaves F. “Hardness of Soft Metals,” Journal, Inst. of Metals, 1928, vol. xxxix, page 301.

Harris F. W. “The Hardness of the Brasses, and Experiments on its Measurement by means of a Strainless Indentation,” Journal, Inst. of Metals, 1922, vol. xxviii, page 327.

Heindlhofer K. “Mechanical and Magnetic Hardness,” The Iron Age, 1925, vol. 116, page 608. Finds that hardened ball-bearing rings, when subjected to a magnetic test, give results which agree with Rockwell test.

Merten W. J. “Wear Resistance of Carburized Steel versus High Manganese Steel,” Trans. Amer. Soc. Steel Treating, 1927, vol. 11, page 233. For these particular tests, case-hardened steel was more resistant to wear than manganese-steel.

Nicollet P. “The Measurement of Hardness by means of the Rockwell Machine,” Revue de Métallurgie Mémoires, 1926, vol. 23, page 575; The Metallurgist (Supplt. to The Engineer), 1926, vol. ii, page 188. Comparison of Brinell, Rockwell, and Herbert pendulum tests.

Ries A. Zimmermann L. “Hardness and Hardness Anisotrophy,” Zeitschrift für Krystallographie, 1923, vol. 57, page 449. Historical account of the scratch hardness test, especially as applied to minerals, is given.

Schneider E. “Comparative Hardness Tests on Tool-Steels when Hot,” Revue de Métallurgie Mémoires, 1922, vol. 19, page 676.

Siebe P. “The Determination of Brinell Hardness of Thin Aluminium Sheets,” Zeitschrift für Metallkunde, 1926, vol. 18, page 295.

Thibaudier L. Viteaux H. “Brinell and Abrasion Tests on Rails,” Revue de Métallurgie Mémoires, 1926, vol. 23, page 65.

“Tests with the ‘Hardness Tongs,’” Le Génie Civil, 1926, vol. 89, page 302; Metallurgist (Supplt. to The Engineer), 1926, vol. ii, page 180. A form of workshop hardness test.