Si元素的添加对快冷Ti合金组织与力学性能的影响

摘要

通过铜模铸造法制备出直径为3mm的（Ti66Ni20Cul3A11）100-xSix（x=0，1，3，5）合金圆柱棒。利用X射线衍射仪（XRD）和扫描电子显微镜（SEM）等研究了Si元素的添加对（Ti66Ni20Cul3Al1）100-xSi，（x=0，1，3，5）（原子百分比）合金组织与力学性能的影响。结果表明：当x=0时，形成Ti基非晶复合材料，塑性应变量达4．5％，同时应力达到1774MPa；当x=1时，试样塑性变形量为3．3％，断裂强度达1825MPa。Si的添加使合金析出脆性相，导致试样破坏性脆断。%The alloy rods with 3 mm in diameter of （Ti66Ni20Cu13A11）100-xSix （x=0, 1, 3, 5） were prepared by copper die casting method. The effects of Si addition on the microstructure and the mechanical properties of （Ti66Ni20Cuz3Al1）100-xSix （x=0, 1, 3, 5） （at%） alloys were investigated mainly by means of X-ray diffraction （XRD） and scanning electric microscopy （SEM）. It was shown that Ti-based amorphous composites are formed （x=0）, the stress and plastic strain of＇the composite are as high as 1774MPa and 4.5%; When x=l, sample with plastic and fracture strength are 3.3% and 1825MPa, respectively. The alloys precipitate brittle phase because of the Si addition, which causes the samples destructive fault by brittle fracture.