【作者】 郭青；

【导师】 王吉会；

【作者基本信息】 天津大学 ， 材料学， 2007， 硕士

【摘要】 金属基复合材料的制备方法和性能研究虽取得了不少进展,但材料的环境协调性并不突出。本文从环境效应考虑,在保持金属材料的力学性能指标基本不变的前提下,使组元单一化,利用钢纤维与铁粉共混设计Fe-Fe复合材料,在达到较高的综合机械性能的同时,也易于循环再生。本文用粉末冶金工艺制备了以316L纤维作为增强体,铁和不锈钢分别作为基体的复合材料。利用正交实验设计方法,探讨了工艺参数对铁基复合材料组织和性能的影响。以密度、硬度、抗拉强度、磨损量、摩擦系数为性能指标,探索出较优的工艺。研究了纤维含量、压制压力、烧结温度对复合材料的显微组织、密度、力学性能及磨损性能的影响,并探讨了其摩擦磨损机理。实验结果表明:纤维含量在3%-5%、压制压力在500MPa-700MPa、烧结温度在1000℃-1200℃时复合材料的性能较好。经正交实验分析获得不锈钢纤维增强纯铁复合材料的最佳工艺参数为:不锈钢纤维含量为5%、初压压力700MPa、烧结温度1000℃。不锈钢纤维增强不锈钢复合材料的最佳工艺参数为:不锈钢纤维含量为7%、初压压力700MPa、烧结温度1100℃。球磨混粉处理能进一步改善复合材料的抗拉强度。粉末冶金法制备不锈钢纤维增强纯铁复合材料的抗拉强度、硬度和耐磨性能较高,密度在7.015-7.217g/cm3左右,硬度约在HRB60-72,纤维含量3%、压制压力为500MPa、1200℃烧结时,复合材料的抗拉强度可达228.63MPa高于纯铁粉35.8MPa。粉末冶金法制备不锈钢纤维增强不锈钢复合材料的效果不明显,密度在6.7-7.0g/cm3左右,硬度较高约在HRB70-90,而耐磨性能较差,纤维含量7%,500MPa,1200℃烧结的复合材料抗拉强度176.25 MPa略高于纯钢粉的抗拉强度。更多还原

【Abstract】 Much progress has been made in preparation and properties of metallic matrix composite these years, but little study focused on the environment compatibility of this kind of materials. In this study, composition of metal base composite had been simplified taking consideration of environment effects, while mechanical properties didn’t change too much. Fe-Fe composite was designed by powder metallurgy using mixture of rustless steel and iron powder for recycling, meanwhile general mechanical behavior should be achieved.Iron and steel base composite reinforced by 316L fibre has been successfully prepared using powder metallurgy. With analysis of orthogonal test, the influences of technology parameter on the microstructure and properties of iron matrix composites have been studied. With the property targets such as density, hardness, tensile strength, frictional wear capacity, friction coefficient, a better technology has been found. The factors affecting the microstructure, density, mechanical properies and friction properties such as fiber content, initial pressure and sintering temperature were elucidated.The resuit of experiment showed that the properties of composite material were better,when fiber content was 3%-5%, initial pressure was 500MPa-700MPa, and sintering temperature was 1000℃-1200℃. Results of orthogonal test showed the optimized processing parameters as followed: fibre content、initial press and sintering temperature were 5%、700Mpa and 1000℃respectively for iron base composite, and 7%、700Mpa and 1100℃respectively for rustless steel base composite.Using powder metallurgy, tensile strength, hardness and wear resistance property of steel fiber base iron composites prepared was high much. When the optimized processing parameters as followed: density、hardness、fiber content、initial pressure and sintering temperature were 7.015-7.217g/cm3, HRB60-72, 3%, 500MPa, and 1200℃, the tensile strength of composite material could achieve 228.63MPa, which was higher that of pure iron powder 35.8MPa. With the method of powder metallurgy, the effect of steel fiber base steel composite prepared was not obvious. When density was 6.7-7.0g/cm3, hardness was HRB70-90, wear resistance property was worse, when fiber was 7%, initial pressure was 500MPa, and sintering temperature was 1200 ℃, tensile strength of composite material was 176.25 MPa, which was a little higher than that of pure steel powder.更多还原