CAJ | 학술논문

研究Al-Mg_2Si合金经250 ℃等通道转角挤压后的微观组织与力学性能.维氏硬度及拉伸力学性能测试结果表明:经4道次ECAP挤压后,Al-Mg_2Si合金的硬度、抗拉强度和延伸率均显著提高;8道次挤压后合金的塑性进一步提高,但其硬度和抗拉强度却有所下降.扫描电子显微镜和透射电子显微镜分析表明:经ECAP挤压后,原汉字状或骨骼状Mg_2Si相显著碎化,且挤压道次越多,Mg_2Si相的破碎效果越明显,合金组织也不断细化.对合金经较多道次挤压后硬度及抗拉强度反而有所下降的原因进行了分析.
연구Al-Mg_2Si합금경250 ℃등통도전각제압후적미관조직여역학성능.유씨경도급랍신역학성능측시결과표명:경4도차ECAP제압후,Al-Mg_2Si합금적경도、항랍강도화연신솔균현저제고;8도차제압후합금적소성진일보제고,단기경도화항랍강도각유소하강.소묘전자현미경화투사전자현미경분석표명:경ECAP제압후,원한자상혹골격상Mg_2Si상현저쇄화,차제압도차월다,Mg_2Si상적파쇄효과월명현,합금조직야불단세화.대합금경교다도차제압후경도급항랍강도반이유소하강적원인진행료분석.
The microstructure and mechanical properties of Al-Mg_2Si alloys by equal channel angular pressing (ECAP) at 250 oC were studied. Vickers hardness and tensile testing show that the hardness, tensile strength and elongation of the alloys increase after ECAP for 4 passes. However, the hardness and tensile strength decrease after ECAP for 8 passes while the elongation increases further. SEM and TEM observations show that the original skelecton shape or the Chinese-script Mg_2Si phase are obviously broken after ECAP. The more the extrusion passes, the more the fragmentated Mg_2Si phase, and the more the alloys refining. The mechanism for the decrease in hardness and tensile strength of the specimen after ECAP for 8 passes compared with 4 passes was discussed.