抛丸处理对ADC12合金挤压铸件表面硬度及粗糙度的影响  

Effects of Shot Blasting on Hardness and Roughness of Surface of ADC12 Alloy Squeeze Casting Parts

作　　者：孟晓欧 吉泽升[1] Meng Xiao＇ou Ji Zesheng(School of Materials Science and Engineering, Harbin University of Science and Technolog)

机构地区：[1]哈尔滨理工大学材料科学与工程学院

出　　处：《特种铸造及有色合金》2017年第3期280-283,共4页Special Casting & Nonferrous Alloys

基　　金：黑龙江省国际合作项目(2015WB15C104);哈尔滨市科技攻关项目(2015AB4AG004)

摘　　要：为了解抛丸处理对ADC12铝合金表面硬度及粗糙度的影响,对ADC12铝合金挤压铸造件进行不同工艺的抛丸处理,测试抛丸前和抛丸后工件的表面粗糙度及硬度,并对表面形貌进行观察分析。粗糙度和硬度测试结果表明,ADC12挤压铸造件抛丸后的粗糙度Ra为2.850~6.515μm,其硬度(HV)由100提高至107~163,并且不同工艺对硬度及粗糙度的影响具有一定的规律性。经抛丸后的试件相当于对表面进行了微锻造,钢丸反复冲击破坏表层原来晶粒组织,使表层组织翻滚产生了大量位错形成表层加工硬化,使试件表面硬度提高,但抛丸处理中产生的缺陷会使表面硬度降低。抛丸速度升高或抛丸时间加长均使试件表面强化层厚度增加,并随着缺陷产生更有利于产生更大的表面起伏,从而使试件粗糙度增大。In order to understand effects of shot blasting treatment on surface hardness and roughness of ADC12 aluminum alloy,the surface hardness and roughness of the samples before and after shot blasting treatment on ADC12 alloy sgueezing casting samples with various processes were measured,and their appearance after shot blasting treatment was observed.The results reveal that the roughness of ADC12 alloy sgueezing casting samples after shot blasting treatment is in range of 2.850-6.515μm,and the hardness（HV）is improved to 107~163from 100.In addition,the test results exhibit a certain patterns in roughness and hardness at various processes.The process of shot blasting treatment is equivalent to conduct micro forging on the surface.The constant impact of steel balls on aluminum alloy changes the original surface crystal structure of the alloy,and causes micro-convection on the surface to generate a lot of dislocation in the structure of surface crystal,which in turn harden the surface of alloy sample.The plastic deformation combined with rougher surface can increase effectively the degree of oxidation to improve the surface hardness.Surface hardness can be decreased due to generation of defects during shot blasting treatment,and with increasing in blasting velocity or blasting time,strengthening layer thickness of sample surface is increased,and it is beneficial to forming the more serious surface wave accompanied with defect formation,which is responsible for roughness increase of sample surface.

关 键 词：ADC12铝合金 挤压铸造 抛丸处理 硬度 粗糙度 

分 类 号：TG249.2[金属学及工艺—铸造]