论文部分内容阅读
对TA15钛合金电子束焊接试样进行充氢,研究了充氢对显微组织形态的影响,并对微量氢对TA15疲劳寿命影响进行考察。显微组织研究表明:充氢量低于0.105%(质量分数)时,氢以固溶态存在于合金中,并未形成氢化物。疲劳试验结果表明:随充氢量的增加,疲劳寿命大幅下降;这是由于微量氢的存在降低了TA15合金的韧性,固溶氢增加了疲劳裂纹的扩展速率,且氢通过影响裂纹尖端的性能加速疲劳裂纹扩展。焊缝区马氏体束呈团状结晶,且以团为单位统一变形,导致断口上呈团簇形态;且氢对马氏体团疲劳扩展中的行为有一定影响。
The TA15 titanium alloy electron beam welding samples were filled with hydrogen, the effect of hydrogen charging on microstructure was studied, and the influence of trace hydrogen on TA15 fatigue life was investigated. Microstructure studies show that: hydrogen charge of less than 0.105% (mass fraction), the hydrogen in the solid solution exists in the alloy, did not form hydride. The results of fatigue tests show that the fatigue life decreases greatly with the increase of hydrogen storage capacity. This is because the presence of trace hydrogen reduces the toughness of TA15 alloy, and the hydrogen storage rate increases the fatigue crack growth rate. Hydrogen influences the performance of the crack tip Accelerate fatigue crack growth. The martensite bundles in the weld zone are in the form of clumps, and are uniformly deformed in the form of clusters, resulting in clusters on the fracture surface. Hydrogen has some influence on the behavior of the martensite clusters during fatigue propagation.