摘要
利用日本网带式连续烧结炉,采用2种不同的烧结工艺制备Cu-20%Zn黄铜,研究烧结工艺对其力学性能和微观组织的影响。第1种烧结工艺是快速升温到550℃预烧50 min,然后在860℃高温烧结50 min;第2种烧结工艺是在200 min内将温度从100℃缓慢升高到750℃,然后升温到870℃保温1 h。结果表明:采用第1种工艺烧结时,烧结体中可看到大量的形状不规则的孔隙,基体没有联接成一体。采用第2种工艺烧结时,由于延长了预烧结时间和减慢升温速度,黄铜的孔隙收缩并趋于球化,孔隙数量明显减少,烧结体的密度和硬度都增大,伸长率显著提高;但由于晶粒长大,晶界强化效果下降,导致强度下降。采用第2种烧结工艺制备的黄铜综合力学性能较好,密度达到8.12 g/cm3,硬度为86 HRH,抗拉强度和伸长率分别为242 MPa和27.3%,均超过日本工业标准JIS和中国国家标准的要求。
Cu-20Zn brass was prepared by powder metallurgy（PM） method.The PM samples were sintered by two processes separately as below： the first is rapid heating to 550 ℃ pre-sintering for 50 min,and then sintering at 860 ℃ for 50 min.The second is slow heating from 100℃ to 750 ℃ in 200 min,and then sintering at 870 ℃ and holding for 1 h.The results show that there are a lot of pores with irregular shape in the alloy after sintered by the first process.After sintered by the second process,since the pre-sintering time is prolonged and the heating speed is slowed down,the number of pores decreases in the alloy,the density and hardness of the sintered alloys increase,and the elongation of them increase greatly as well;however,the effects of grain boundary strengthening decrease because of the growth of grains,which results in the strength of Cu-20Zn alloy decrease.Cu-20Zn alloy sintered by the second process has good comprehensive mechanical properties.The density,hardness,tensile strength and elongation are 8.12 g/cm^3,86HRH,242 MPa and 27.3%,respectively.All of these properties exceed the Japanese industrial standard（JIS） and Chinese national standard（GB）.
出处
《粉末冶金材料科学与工程》
EI
2010年第5期491-494,共4页
Materials Science and Engineering of Powder Metallurgy
关键词
粉末冶金
黄铜
烧结
力学性能
微观组织
powder metallurgy
brass
sintering
mechanical properties
microstructure
