Ti_3Al基合金的弹性变形能与空蚀

Elastic deformation energy and cavitation erosion of Ti_3Al-based alloy

利用旋转圆盘装置研究了Ti3 Al基合金Ti 2 4Al 15Nb 1Mo的空蚀行为 ,并用洛氏硬度仪模拟空蚀过程中微射流所产生的局部载荷对Ti 2 4Al 15Nb 1Mo合金的作用 ,测量了压头加载过程中该合金吸收的总能量和弹性变形能 (选择我国水利机械常用 0Cr13Ni5Mo马氏体不锈钢作对比材料 )。结果表明 :Ti 2 4Al 15Nb 1Mo合金的抗空蚀性能优于 0Cr13Ni5Mo不锈钢 ,空蚀 40h后前者的累积体积损失量仅为 0 .5 5 1mm3 ,而后者的累积体积损失量达到2 .6 15mm3 ;在局部载荷作用下 ,Ti 2 4Al 15Nb 1Mo合金不仅有较高的加工硬化能力 ,而且有较好的弹性性能 ;在压痕试验中其弹性变形能在总变形能量中所占比例达到 1/ 3。这些性能特点使Ti 2 4Al 15Nb 1Mo合金在空蚀过程中能吸收和释放较多的冲击能量 ,延缓裂纹形成 ,减少体积损失 ,呈现良好的抗空蚀性能。

The cavitation erosion of Ti 3Al-based alloy Ti-24Al-15Nb-1Mo was investigated by using rotating disc equipment. To simulate the effect of the collapse of vapor cavities or bubbles, Rockwell hardness tester was used to exert a load on the small area of Ti-24Al-15Nb-1Mo alloy, and the total deformation energy and elastic deformation energy of the test material were determined. Martensitic stainless steel 0Cr13Ni5Mo was chosen for comparison. The results show that the cavitation erosion resistance of the Ti-24Al-15Nb-1Mo alloy is better than that of the 0Cr13Ni5Mo stainless steel. After 40 h of exposure to cavitation erosion, the cumulative volume loss of the former is only 0.551 mm 3, while that of the latter is 2.615 mm 3. Ti-24Al-15Nb-1Mo alloy has good work-hardening ability and elasticity. Its elastic deformation energy approaches 1/3 of the total deformation energy in indentation test. All these characteristics make it absorb and relieve more impact energy in cavitation erosion, thus reducing volume loss, and showing excellent cavitation erosion resistance.