CAJ | 학술논문

研究焊接电流对涂覆TiO2活性剂AZ31镁合金板材活性钨极氩弧焊(A-TIG)焊接接头的宏观形貌、微观结构和力学性能的影响。实验结果表明，随着焊接电流的增加，焊缝的熔深和熔宽比增加，涂覆TiO2的焊缝表面形貌逐渐恶化；焊缝中α-Mg 晶粒尺寸增加，颗粒状β-Mg17Al12数量增多。与普通的TIG焊相比，A-TIG焊缝熔深明显增加并且晶粒尺寸粗化。当焊接电流小于130 A时，涂覆TiO2焊接接头的极限抗拉强度值随着焊接电流的增加而增加，当焊接电流超过130 A时其抗拉强度值开始下降；焊缝热影响区和熔合区的平均显微硬度随着焊接电流的增加逐渐降低。
연구한접전류대도복TiO2활성제AZ31미합금판재활성오겁아호한(A-TIG)한접접두적굉관형모、미관결구화역학성능적영향。실험결과표명，수착한접전류적증가，한봉적용심화용관비증가，도복TiO2적한봉표면형모축점악화；한봉중α-Mg 정립척촌증가，과립상β-Mg17Al12수량증다。여보통적TIG한상비，A-TIG한봉용심명현증가병차정립척촌조화。당한접전류소우130 A시，도복TiO2한접접두적겁한항랍강도치수착한접전류적증가이증가，당한접전류초과130 A시기항랍강도치개시하강；한봉열영향구화용합구적평균현미경도수착한접전류적증가축점강저。
The effects of welding current on the macro-morphology, microstructure and mechanical properties of tungsten inert gas (TIG) welded AZ31 magnesium alloy joints with TiO2 coating were investigated. The results showed that the increase of welding current led to the increase in the depth/width ratio and deteriorated the surface appearance of the welded seams with TiO2 coating. The grain size ofα-Mg and the amount of granularβ-Mg17Al12 particles in the welded seams also increased. The welded joints with TiO2 coating exhibited a deeper weld penetration and larger grain size compared with the welded joint without TiO2 coating. When the welding current was less than 130 A, the ultimate tensile strength of the welded joints with TiO2 coating increased with the increase in welding current and then decreased when the welding current was greater than 130 A. The average microhardness of the heat-affected zone and fusion zone decreased gradually with the increase of welding current.