模具加工：方法(fa)是(shi)多种多样的,下(xia)面(mian)我们来分析(xi)一下(xia)有关电(dian)火花成形加工(gong)(gong)(gong)方法(fa)知识。电(dian)火花成形加工(gong)(gong)(gong)主(zhu)要是(shi)利用(yong)在(zai)工(gong)(gong)(gong)具和工(gong)(gong)(gong)件(jian)(正、负电(dian)极)之间产生脉冲性火花放电(dian)时的电(dian)腐蚀(shi)现象(xiang)来蚀(shi)除多余的金属,以达到零件(jian)技(ji)术要求所规定的尺寸、形状(zhuang)及表面(mian)质量(liang)。

1、模具电火花成形(xing)加工方法(fa)必须满足三大条件:

①必(bi)须(xu)使工(gong)(gong)具(ju)(ju)电(dian)极和(he)工(gong)(gong)件被加工(gong)(gong)表面之间(jian)保持一(yi)定的间(jian)隙,因此在电(dian)火花加工(gong)(gong)中必(bi)须(xu)具(ju)(ju)有(you)工(gong)(gong)具(ju)(ju)电(dian)极的自动进给和(he)调节装(zhuang)置;

②火花放(fang)电(dian)(dian)必须(xu)(xu)是瞬时的脉(mai)冲性(xing)放(fang)电(dian)(dian),为(wei)此电(dian)(dian)火花加(jia)工必须(xu)(xu)使用脉(mai)冲电(dian)(dian)源;

③火花放电必(bi)须在有一定绝缘性能的液体(ti)介质中进行(xing)。

2、影响电火(huo)花(hua)成形蚀除速(su)率的因素:电规准(zhun)、极(ji)性效应、金属材料的热学常数(shu)、工作液、排屑条件。

3、影响电(dian)火(huo)花(hua)成形(xing)加工(gong)(gong)精度的因素(su):机床(chuang)本(ben)身的各种误差、工(gong)(gong)具(ju)电(dian)极制造精度、工(gong)(gong)件(jian)和电(dian)极的定位及安装误差、放电(dian)间隙的大(da)小(xiao)和一致(zhi)性、工(gong)(gong)件(jian)电(dian)极的损(sun)耗(hao)及其加工(gong)(gong)稳定性。

4、电(dian)火花(hua)加(jia)工(gong)的电(dian)极材(cai)料要求:损耗小(xiao)、加(jia)工(gong)过程稳定、生产率高(gao)、机械加(jia)工(gong)性能好(hao)、价格(ge)低廉(lian)。常用材(cai)料:紫铜、石墨、铸铁、钢、黄铜、同钨(wu)合(he)金(jin)、银(yin)钨(wu)合(he)金(jin)。

结(jie)构(gou)形式(shi):①整(zheng)体式电极②镶拼式电极③组(zu)合电极。

5、电火(huo)花成形加工型腔模的(de)方法:

①单电极平(ping)动法(fa)②多电(dian)极(ji)更换法③分解电极法。