分别借鉴脉冲电流与激光各自的优势对钛合金中的深层裂纹进行复合处理，研究脉冲电流-激光愈合处理对力学性能的影响机理。微观硬度检测结果显示，经过脉冲电流处理后，愈合区与基体间硬度差异明显，愈合区具有较高的硬度值；经过激光重熔处理后，由脉冲电流处理形成的愈合区内硬度有所下降，且在重熔区-热影响区-基体内硬度呈现出逐渐递减的趋势。力学性能测试结果显示，对脉冲电流处理试样，拉伸性能降低，疲劳性能提升，且性能曲线均呈现二次断裂特性，这是由于愈合区的塑性较低，且处于应力集中区域，在加载过程中造成愈合区提前断裂或失效。对脉冲电流与激光复合处理试样，拉伸与疲劳性能提升明显。脉冲电流的绕流效应、焦耳热效应及激光的重熔作用是实现裂纹愈合效果的主要原因。
邓德伟
,
于涛
,
张林
,
杨树华
,
张洪潮
. 脉冲电流-激光愈合钛合金深层裂纹愈合处理对力学性能的影响机理研究[J]. 机械工程学报, 2017
, 53(18)
: 93
-98
.
DOI: 10.3901/JME.2017.18.093
The effect of healing on mechanical properties is investigated by the combined treatment of pulse current and laser applied to deep crack in titanium alloy, as they have different advantages in crack healing. The micro-hardness test results show that after electropulsing treatment the hardness between substrate and healing areas is significantly different, and the higher hardness is observed in healing areas. After laser remelting treatment, the hardness of healing areas generated in electropulsing treatment process is reduced and the hardness among remelting zone-heat affected zone-substrate shows a gradual decreasing trend. The mechanical test results show that, for electropulsing treatment specimen, the tensile property decreases and the fatigue property increases, both the mechanical performance curves show the secondary fracture properties. While for the specimen experienced the combined treatment of pulse current and laser, both the tensile and fatigue properties are improved obviously. The detour and joule heating effect of pulse current and the remelting effect of laser are the main reasons to realize crack healing.
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