The importance of correct diagnosis is explained, and reasons given why primary failure may have to be isolated from secondary damage. The importance of prior information on design, manufacture, and service conditions is discussed, and also how much information is often yielded from a close inspection of the failed components, by eye and with the aid of optical and electron microscopes. The need for careful cleaning of fracture surfaces is stressed. Cases when metallographical investigation, mechanical tests, and chemical analysis may be required are considered, and occasions when crack detection techniques may be useful. Types of failure are listed, with causes and examples. As prevention is better than cure, inspection techniques useful in the diagnosis of impending failure are described.
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References
1.
CritesN. A.‘Which type of stress analysis method?’, Product Engng196132 (39), 90.
ThorntonD. R.Scanning electron microscopy1968 (Chapman & Hall, London).
7.
BarwellF. T.ScottD.‘The investigation of unusual bearing failures’, Paper 10, Lubric. and Wear Fourth Conv., Proc. Instn mech. Engrs1965–66180 (Pt 3K), 277.
8.
MooreA. J. W.‘A refined metallographic technique for the examination of surface contours and surface structure of metals’, Metallurgia194838 (224), 71.
9.
MelfordD. A.DuncombP.‘The application of X-ray scanning microanalysis to some metallurgical problems’, Metallurgia196061 (367), 205.
10.
De LeirisH.MencarelliE.JacquetP. J.‘Techniques for removing rust from fractures in steel components intended for electronmicro-fractography’ (in French), Mem. Scient. Rev. Métall196663 (5), 463.
11.
ScottD.LoyB.McCallumR.MillsG. H.‘Electron optical techniques of failure investigation’, Paper 4 of this conference.
12.
KiesJ. A.SullivanA. M.IrwinG. R.‘Interpretation of fracture markings’, J. appl. Phys.195021 (7), 716.
BoydG. M.‘The propagation of fracture in mild steel plates’, Engineering, Lond.1953175 (4538), 65; (4539), 100.
15.
SplittgerberE.‘Internal stresses in components as causes of failure’ (in German), Maschinenschaden196841 (4), 135.
16.
FieldJ. E.WatersD. M.‘Fretting-fatigue strength of En 26 steel’, N.E.L. Rept 275 1967 (National Engineering Laboratory, East Kilbride, Glasgow).
17.
JacobyG.‘Fractographic methods in fatigue research’, Exp. Mech.19655 (3), 65.
18.
CottellG. A.‘Lessons to be learnt from failures in service’, Proc. Int. Conf. on Fatigue of Metals 1957, 563 (Instn Mech. Engrs, London).
19.
LoveR. J.‘Fatigue in automobiles’, Proc. Int. Conf. on Fatigue of Metals 1957, 570 (Instn Mech. Engrs, London).
20.
FieldJ. E.‘Effect of direction of fretting on the fretting-fatigue strength of L65 aluminium alloy’, N.E.L. Rept 120 1963 (National Engineering Laboratory, East Kilbride, Glasgow).
21.
WidnerR. L.WolfeJ. O.‘Valuable results from bearing damage analysis’, Metal Prog.196893 (4), 79.
22.
ScottD.‘The effect of material properties, lubricant and environment on rolling contact fatigue’, Paper 10, Proc. Symp. on Fatigue in Rolling Contact 1964, 103 (Instn Mech. Engrs, London).
23.
AllanR. K.Rolling bearings1964 (Pitman, London).
24.
PalmgrenA.Ball and roller bearing engineering1945 (S.K.F. Industries, Philadelphia).
25.
SimpsonF. F.‘Failure of rolling contact bearings’, Paper 8, Lubric. and Wear Second Conv., Proc. Instn mech. Engrs1963–64178 (Pt 3N), 215.
26.
GrunbergL.JamiesonD. T.ScottD.‘Hydrogen penetration in water-accelerated fatigue of rolling surfaces’, Phil. Mag.19638 (93), 1553.
27.
ScottD.‘Effect of environment on bearing performance’, Paper 4, Symp. on Corrosion and its Prevention in Motor Vehicles, Proc. Instn mech. Engrs1967–68182(Pt 3J), 116.
28.
RafiqueS. O.‘Failures of plain bearings and their causes’, Paper 15, Lubric. and Wear Second Conv., Proc. Instn mech. Engrs1963–64178 (Pt 3N), 180.
29.
ScottD.‘Metallurgical aspects of wear’, Paper 1, Symp. on Lubrication in Textile Machinery, Proc. Instn mech. Engrs1966–67181 (Pt 3L), 39.
30.
ScottD.‘Techniques for the investigation of debris and lubricant contaminants’, Symp. on Experimental Methods in Tribology, Proc. Instn mech. Engrs1967–68182 (Pt 3G), 83.
British Rail‘Cavitation corrosion and its prevention in diesel engines’, 1965 (British Rail Chemical Research Division, London).
33.
HobbsJ. M.‘Avoidance of cavitation erosion in turbo-machines’, Paper SP 931, B.H.R.A. 9th Members Conf. 1967 (September) (British Hydromechanics Research Association, Cranfield).
34.
BezerH. J.‘Magnetic methods of non-destructive testing’, Br. J. Non-destructive Test.19646 (3), 85; 1964, 109, 119.
35.
DoaneF. B.BetzC. E.Principles of magnaflux (Magnaflux Corp., Chicago).
36.
CookW. G.‘Problems and progress in the use of penetrant methods of flaw detection’, in Progress in applied materials research (Eds StanfordE. G.FearonI. H.) 19624, 227 (Heywood, London).
37.
VignessI.‘Application of electrical methods for the detection of flaws and for the study of metal structures’, in Progress in applied materials research (Eds StanfordE.G.FearonI. H.) 19622, 61 (Heywood, London).
38.
ClaydonD. G. W.‘Defect assessment using ultrasonic waves’, in Progress in applied materials research (Eds StanfordE. G.FearonI. H.) 19622, 165 (Heywood, London).
39.
HalmshawR.PollittC. G.‘Radiology with high energy X-rays’, in Progress in applied materials research (Eds StanfordE. G.FearonI. H.) 19622, 1 (Heywood, London).
