【摘要】 用已原位钛合金化的电解低钛铝基合金熔配了内燃机活塞常用的不同钛含量(ωTi=0-0.23％)的ZL108合金,进行了合金的成分分析和组织观察,结果表明:随着钛含量的增加,一次和二次枝晶发生了由比较粗大→细小→组大的变化,一次枝晶长度变化不大,二次枝晶发生了由长变短的变化;同时,二次枝晶臂间距和共晶硅颗粒的直径也发生了由大到小而后又增大的变化,在ωTi=0.11％,最小值分别为16.7μm和2.7μm。在ωTi=0.11％-0.16％之间存在着最佳的钛含量,为进一步研究该合金的性能以及工业化生产优质高性能的活塞材料提供了理论和实验依据。更多还原

【Abstract】 The Al-Si ZL108 alloys with 0 - 0.23% of mass fractions of titanium for piston material of internal combustion engine are produced by using the electrolytic lower titanium Al alloys of in-situ titanium alloying. The composition and microstructure of the alloy are analyzed and observed. The results show that with the increase of titanium content,the sizes of first and second dendrites of α-Al change from larger to finer then again larger,and the length of first dendrite has little changes, but the length of second dendrites changes from long to short. Meanwhile, the second dendrite arm spacing (DAS) of α-Al,and the average size of eutectic Si particles change from big to small then big. When the mass fraction of titanium is 0.11 % , the minimum second DAS and the diameter of eutectic Si particle are 16. 7μm and 2.7μm respectively. This indicates that within the range of 0.11 % -0.16% of mass fraction of titanium, the optimal titanium content exists. All these provide the theoretical and experimental foundation for further research of the alloy properties and the industrial production of the new type of Al piston material of excellent property and high quality.更多还原