A new type of composite refiner Ti/TiCN is prepared by loading submicron-TiCN particles onto Ti micron-particles and added to industrial pure aluminium. Refining mechanism has been characterised in detail by optical microscopy, scanning electron microscopy and transmission electron microscopy coupled with energy disperse X-ray spectra. These experimental results show that Ti/TiCN inoculation is more effective in refining pure aluminium than Ti and TiCN added separately. The relationship between grain size and growth restriction factors of aluminium matrix containing Ti/TiCN refiner is d = 70.2 + 1190.8/Q. According to the free growth theory, aluminium matrix with Ti/TiCN inoculation has the largest solidification driving force to promote grain nucleation under the same growth restriction factors (Q = 0.5,1, 5, 12, 20 K) compared to Ti and TiCN refiners.
KnowlesAJJiangXGalanoMMicrostructure and mechanical properties of 6061 Al alloy based composites with SiC nanoparticles. J Alloys Compd. 2014; 615:S401–S405.
2.
TroncheAVandyoussefiMGreerAL.Instability of TiC particle in aluminium melts inoculated with an Al–Ti–C grain refiner. Mater Sci Technol. 2002; 18:1072–1078.
3.
LiPLiuSZhangLGrain refinement of A356 alloy by Al–Ti–B–C master alloy and its effect on mechanical properties. Mater Des. 2013; 47:522–528.
4.
WangKCuiCWangQFabrication of in situ AlN–TiN/Al inoculant and its refining efficiency and reinforcing effect on pure aluminum. J Alloys Compd. 2013; 547:5–10.
5.
SuHGaoWFengZProcessing, microstructure and tensile properties of nano-sized Al2O3 particle reinforced aluminum matrix composites. Mater Des. 2012; 36:590–596.
6.
WangFEskinDMiJA refining mechanism of primary Al3Ti intermetallic particles by ultrasonic treatment in the liquid state. Acta Mater. 2016; 116:354–363.
7.
LuZGuoCLiPEffect of electropulsing treatment on microstructure and mechanical properties of intermetallic Al3Ti alloy. J Alloys Compd. 2017; 708:834–843.
8.
FanZWangYZhangYGrain refining mechanism in the Al/Al–Ti–B system. Acta Mater. 2015; 84:292–304.
9.
WangTGaoTNieJInfluence of carbon source on the microstructure of Al–Ti–C master alloy and its grain refining efficiency. Mater Charact. 2013; 83:13–20.
10.
SunHWuJTangTEffect of vanadium carbide on commercial pure aluminum. Int J Min Metall Mater. 2017; 24:833–841.
11.
WangYShenaPGuoRFDeveloping high toughness and strength Al/TiC composites using icetemplating and pressure infiltration. Ceram Int. 2017; 43:3831–3838.
12.
ShinJHJeonJHBaDH.Microstructure refining of aluminum alloys using aluminothermic reaction with ZnO nanoparticles. Mater Lett. 2015; 151:96–99.
13.
ZhangLWangZLiQMicrotopography and mechanical properties of vacuum hot pressing Al/B4C composites. Ceram Int. 2018; 44:3048–3055.
14.
ShonI-J.Effect of Al on sintering and mechanical properties of WC-Al composites. Ceram Int. 2016; 42:17884–17891.
15.
ReddyMPUbaidFShakoorRAEffect of reinforcement concentration on the properties of hot extruded Al–Al2O3 composites synthesized through microwave sintering process. Mater Sci Eng A. 2017; 696:60–69.
16.
YeCYueXJiangYEffect of different preparation methods on the microstructure and mechanical properties of Si3N4 ceramic composites. Ceram Int. 2018; 44:3664–3671.
17.
NingJLJiangDMFanJZGrain refinement in as cast Al–Mg–Mn alloy during high temperature equal channel angular pressing. Mater Sci Technol. 2009; 25:820–828.
18.
XuZWangXLiangDElectric current pulse induced grain refinement in pure aluminium. Mater Sci Technol. 2015; 31:1595–1600.
19.
LiXCaiQZhaoBGrain refining mechanism in pure aluminum with nanosized TiN/Ti composite refiner addition. J Alloys Compd. 2017; 699:283–290.
20.
LekatouAKarantzalisAEEvangelouAAluminium reinforced by WC and TiC nanoparticles (ex-situ) and aluminide particles (in-situ): microstructure, wear and corrosion behaviour. Mater Des. 2015; 65:1121–1135.
21.
CrossleyFAMondolfoLF.Mechanism of grain refinement in aluminum alloys. J Met Trans Am Inst Min Metall Petrol Eng. 1951; 191:1143–1148.
22.
DaviesIGDennisJMHellawellA.The nucleation of aluminum grains in alloys of aluminum with titanium and boron. Metall Trans A. 1970; 1:275–280.
23.
CibulaA.The mechanism of grain refinement of sand castings in aluminum alloys. J Inst Met. 1949; 76:321–360.
24.
JonesGPPearsonJ.Factors affecting grain refinement of aluminium using Ti and B additives. Metall Mater Trans B. 1976; 7:223–234.
25.
JonesGP. The mechanism of nucleation of liquid aluminium by Al–Ti–B master alloys. International Seminar on Refining and Alloying of Liquid Aluminium and Ferro-Alloy; Trondheim, Norway. 1985. p. 213–228.
26.
JonesGP. ‘Solidification processing 1987’ of metals. London: The Institute of Metals; 1988. p. 496–499.
27.
SchumacherPGreerAL.Heterogeneously nucleated α-Al in amorphous aluminium alloys. Mater Sci Eng A. 1994; 178:309–313.
28.
MohantyPSGruzleskJE.Mechanism of grain refinement in aluminium. Acta Metall Mater. 1994; 43:2001–2012.
29.
SunYLuCYuHNanomechanical properties of TiCN and TiCN/Ti coatings on Ti prepared by filtered Arc deposition. Mater Sci Eng A. 2015; 625:56–64.
30.
KotenMAMukherjeePShieldJE.Core–shell nanoparticles driven by surface energy differences in the Co–Ag, W–Fe, and Mo–Co systems. Part Part Syst Charact. 2015; 32:848–853.
31.
ZhangM-XKellyPMEastonMACrystallographic study of grain refinement in aluminum alloys using the edge-to-edge matching model. Acta Mater. 2005; 53:1427–1438.
32.
NikitinVIWanqiJIEKandalovaEGPreparation of Al–Ti–B grain refiner by shs technology. Scr Mater. 2000; 42:561–566.
33.
JohnssonM.Grain refinement of aluminium studied by use of a thermal analytical technique. Thermochim Acta. 1995; 256:107–121.
34.
EastonMStJohnDH.An analysis of the relationship between grain size, solute content, and the potency and number density of nucleant particles. Metall Mater Trans A. 2004; 36A:1911–1920.
35.
EastonMAStJohnDH.A model of grain refinement incorporating alloy constitution and potency of heterogeneous nucleant particles. Acta Mater. 2001; 49:1867–1878.
36.
StJohnDHQianMEastonMAGrain refinement of magnesium alloys. Metall Mater Trans A. 2005; 36A:1669–1679.
37.
MaxwellIHellawellA.A simple model for grain refinement during solidification. Acta Metall. 1975; 23:229–237.
38.
DesnainPFautrelleYMeyerJLPrediction of equiaxed grain density in multicomponent alloys, stirred electromagnetically. Acta Metall Mater. 1990; 38:1513–1523.
39.
JohnssonMBackerudLSigworthGK.Study of the mechanism of grain refinement of aluminum after additions of Ti- and B-containing master alloys. Metall Trans A. 1992; 24:481–491.
40.
WangKJiangHWangQA novel method to achieve grain refinement in aluminum. Metall Mater Trans A. 2016; 47A:4788–4794.
41.
WangFLiuZQiuDThe influence of the effect of solute on the thermodynamic driving force on grain refinement of Al alloys. Metall Mater Trans A. 2015; 46A:505–515.
42.
StJohnDHQianMEastonMAThe interdependence theory: the relationship between grain formation and nucleant selection. Acta Mater. 2011; 59:4907–4921.
