TC18超高强度钛合金喷丸残余压应力场的研究

Residual Compressive Stress Field in TC18 Ultra-high Strength Titanium Alloy by Shot Peening

采用 X 射线衍射及相应交相关定峰法,通过电解抛光逐层测定了 TC18 超高强度钛合金喷丸的残余压应力,并分析了残余压应力场的特征及规律,同时研究了在交变应力和温度下残余压应力的松弛,结果表明,残余压应力场中的最大值为材料的本征参数,它与喷丸强化工艺无关,这对超高强度钛合金喷丸工艺的制定和应用具有重要意义。

yUsing X-ray diffraction and the cross correlation method to determine the peak of diffraction plane (114), the residual stress distribution along the surface layer in the titanium alloy TC18 caused by shot peening was measured during step-by-step electrolytic dissolution. Relaxation of the compressive residual stress caused by shot peening at high temperatures and during cyclic stress was investigated. The characteristics of residual compressive stress field have also been analyzed; it was determined that the maximum compressive residual stress is a intrinsic parameter that is not affected by shot peening. From the above experimental results some practical laws have been derived, which offers a basis for the shot peening processing decision as it applies to the TC 18 titanium alloy.