CAJ | 학술논문

采用粉末热挤压法制备硼酸镁晶须增强铝基复合材料，研究不同挤压比对挤压态复合材料微观组织和性能的影响。结果表明：随着挤压比的增加，硼酸镁晶须的排布取向逐渐趋向于材料的热挤压方向，晶须长径比有所减小，挤压比为25：1时，材料力学性能达到最佳值，屈服强度、极限拉伸强度及伸长率分别为113.5 MPa、230 MPa和7.0%；拉伸强度(UTS)相比挤压态的6061铝合金和挤压比为9：1的复合材料分别提高了37%和25%；拉伸断口分析表明，材料的失效形式以6061Al基体的韧性断裂、晶须与基体间的脱粘以及晶须团聚体的脆性开裂3种形式为主。
채용분말열제압법제비붕산미정수증강려기복합재료，연구불동제압비대제압태복합재료미관조직화성능적영향。결과표명：수착제압비적증가，붕산미정수적배포취향축점추향우재료적열제압방향，정수장경비유소감소，제압비위25：1시，재료역학성능체도최가치，굴복강도、겁한랍신강도급신장솔분별위113.5 MPa、230 MPa화7.0%；랍신강도(UTS)상비제압태적6061려합금화제압비위9：1적복합재료분별제고료37%화25%；랍신단구분석표명，재료적실효형식이6061Al기체적인성단렬、정수여기체간적탈점이급정수단취체적취성개렬3충형식위주。
The Mg 2 B 2 O 5 whisker reinforced Al matrix composites were fabricated using powder metallurgy routes. The effects of different extrusion ratios on the microstructure and tensile strength of composites were investigated. The results show that the alignment of Mg2B2O5 whisker along the extrusion direction is improved and the aspect ratio decreases with increasing extrusion ratio, meanwhile, the composites exhibit the best mechanical properties at the extrusion ratio of 25:1. Respectively, the yield strength, the tensile strength and the elongation of the extruded composites is 113.5 MPa, 230 MPa and 7.0%. The tensile strength increases by 37%and 25%, in comparison with the aluminum and composites. According to the analysis of fracture, the ductile failure of 6061Al matrix, the reinforcement fracture and the whisker-matrix interface debonding act as the main mechanism of fracture nucleation.