激光表面硬化工艺对TC4钛合金表面硬度和硬化层深度的影响

Effect of Laser Surface Hardening Processes on Surface Hardness and Hardening Depth of TC4 Titanium Alloy

对TC4钛合金分别进行了真空固溶和时效处理及激光固溶和时效处理的试验。结果表明:TC4合金950℃真空固溶处理随后520℃时效处理后的硬度平均为39.7 HRC,经工艺(1)激光固溶处理随后540℃时效处理后的合金硬度为51.3 HRC,后者比前者高11.6 HRC;经工艺(2)激光固溶处理随后500℃时效处理后的TC4合金硬度为44.4 HRC,比真空固溶处理随后时效处理的合金高4.7 HRC;经工艺(1)激光固溶处理的TC4合金硬化层深度约为0.3 mm,经工艺(2)激光固溶处理的合金硬化层深度约为0.2 mm;经工艺(1)激光固溶处理的合金表面发生重熔,硬度波动较大。

TC4 titanium alloy was subjected to vacuum solid solution and aging treatments and to laser solid solution and aging treatments,respectively.The results showed that(a)the TC4 alloy exhibited average hardness of 39.7 HRC after vacuum solution treating at 950℃followed by aging at 520℃,and hardness of 51.3 HRC after laser solution treating with process①followed by aging at 540℃,the latter was 11.6 HRC higher than the former;(b)the TC4 alloy exhibited hardness of 44.4 HRC after laser solution treating with process②followed by aging at 500℃,which was 4.7 HRC higher than that of the TC4 alloy after vacuum solid solution treating followed by aging;(c)the hardening depth of the TC4 alloy was 0.3 mm after laser solution treating with process①and 0.2 mm after solid solution treating with process②;and(d)the surface of the TC4 alloy laser solid solution treated by process①showed remelting phenomenon and greatly fluctuant hardness.