夜夜穞天天穞狠狠穞AV美女按摩

螺(luo)母(mu)便是螺(luo)帽(mao)，与(yu)螺(luo)栓或螺(luo)杆(gan)拧在一起用(yong)来起紧(jin)固作(zuo)用(yong)的(de)零(ling)件(jian)，所有生产(chan)制(zhi)造机械必(bi)须用(yong)的(de)一种原件(jian)。铜(tong)(tong)螺(luo)母(mu)的(de)定(ding)义便是使用(yong)铜(tong)(tong)材质制(zhi)作(zuo)的(de)螺(luo)母(mu)，我们日常接(jie)触到的(de)的(de)铜(tong)(tong)螺(luo)母(mu)主要(yao)是六角螺(luo)母(mu)或是与(yu)螺(luo)栓相(xiang)配(pei)的(de)其(qi)它铜(tong)(tong)螺(luo)母(mu)。

因(yin)为铜螺(luo)母(mu)具(ju)有不易(yi)生锈(xiu)、防(fang)腐(fu)蚀、易(yi)导热及导电性强(qiang)等(deng)优(you)点(dian)，一般用于防(fang)锈(xiu)，高温(wen)、导电、导热等(deng)使用环境下，如水龙头(tou)，阀门，电器开(kai)关(guan)等(deng)。铜螺(luo)母(mu)的(de)另一主要(yao)的(de)用途是(shi)注(zhu)(zhu)塑，加热后嵌(qian)入到塑料件里面或是(shi)直接模具(ju)注(zhu)(zhu)塑。高强(qiang)度(du)自锁铜螺(luo)母(mu)具(ju)有强(qiang)度(du)高、可靠性强(qiang)等(deng)优(you)点(dian)，为自锁螺(luo)母(mu)的(de)一个(ge)分类(lei)。

大(da)型(xing)螺(luo)母的(de)(de)(de)主要材质是(shi)铝(lv)青(qing)(qing)铜(tong)(tong)(tong)(tong)和锡(xi)(xi)(xi)青(qing)(qing)铜(tong)(tong)(tong)(tong)。铝(lv)青(qing)(qing)铜(tong)(tong)(tong)(tong)是(shi)由铝(lv)元(yuan)素(su)(su)为主加(jia)(jia)元(yuan)素(su)(su)的(de)(de)(de)铜(tong)(tong)(tong)(tong)铝(lv)合(he)金，但含(han)铝(lv)量(liang)一般不(bu)超(chao)过(guo)1.5%，有时(shi)还加(jia)(jia)入适量(liang)的(de)(de)(de)铁(tie)、镍、锰(meng)等(deng)元(yuan)素(su)(su)。铝(lv)青(qing)(qing)铜(tong)(tong)(tong)(tong)有比锡(xi)(xi)(xi)青(qing)(qing)铜(tong)(tong)(tong)(tong)高(gao)的(de)(de)(de)机(ji)(ji)械(xie)性(xing)(xing)(xing)(xing)能(neng)和耐(nai)(nai)磨、耐(nai)(nai)蚀(shi)、耐(nai)(nai)寒、耐(nai)(nai)热、无(wu)铁(tie)磁(ci)性(xing)(xing)(xing)(xing)，有良好(hao)(hao)(hao)的(de)(de)(de)流动性(xing)(xing)(xing)(xing)，无(wu)偏析倾(qing)向(xiang)，可(ke)得到致(zhi)密(mi)的(de)(de)(de)铸件。在铝(lv)青(qing)(qing)铜(tong)(tong)(tong)(tong)中加(jia)(jia)入铁(tie)、镍和锰(meng)等(deng)元(yuan)素(su)(su)，可(ke)进一步改善(shan)合(he)金的(de)(de)(de)各种(zhong)性(xing)(xing)(xing)(xing)能(neng)。锡(xi)(xi)(xi)青(qing)(qing)铜(tong)(tong)(tong)(tong)是(shi)由锡(xi)(xi)(xi)为主加(jia)(jia)元(yuan)素(su)(su)的(de)(de)(de)铜(tong)(tong)(tong)(tong)锡(xi)(xi)(xi)合(he)金，含(han)锡(xi)(xi)(xi)量(liang)一般在3～14%之间。锡(xi)(xi)(xi)青(qing)(qing)铜(tong)(tong)(tong)(tong)的(de)(de)(de)耐(nai)(nai)磨性(xing)(xing)(xing)(xing)耐(nai)(nai)蚀(shi)性(xing)(xing)(xing)(xing)很好(hao)(hao)(hao)。锡(xi)(xi)(xi)青(qing)(qing)铜(tong)(tong)(tong)(tong)有较(jiao)(jiao)高(gao)的(de)(de)(de)机(ji)(ji)械(xie)性(xing)(xing)(xing)(xing)能(neng)，较(jiao)(jiao)好(hao)(hao)(hao)的(de)(de)(de)耐(nai)(nai)蚀(shi)性(xing)(xing)(xing)(xing)、减摩性(xing)(xing)(xing)(xing)和好(hao)(hao)(hao)的(de)(de)(de)铸造(zao)性(xing)(xing)(xing)(xing)能(neng)；对过(guo)热和气体的(de)(de)(de)敏感性(xing)(xing)(xing)(xing)小(xiao)，焊接性(xing)(xing)(xing)(xing)能(neng)好(hao)(hao)(hao)，无(wu)铁(tie)磁(ci)性(xing)(xing)(xing)(xing)，收缩(suo)系数小(xiao)。锡(xi)(xi)(xi)青(qing)(qing)铜(tong)(tong)(tong)(tong)10-1铸造(zao)铜(tong)(tong)(tong)(tong)合(he)金硬(ying)度(du)高(gao)，耐(nai)(nai)磨性(xing)(xing)(xing)(xing)极(ji)好(hao)(hao)(hao)，不(bu)易(yi)产生咬死现象，有较(jiao)(jiao)好(hao)(hao)(hao)的(de)(de)(de)铸造(zao)性(xing)(xing)(xing)(xing)能(neng)和切削(xue)加(jia)(jia)工性(xing)(xing)(xing)(xing)能(neng)，在大(da)气和淡水中有良好(hao)(hao)(hao)的(de)(de)(de)耐(nai)(nai)蚀(shi)性(xing)(xing)(xing)(xing)。

离心(xin)(xin)铸造压下(xia)螺母的特点是金(jin)属液在离心(xin)(xin)力作用(yong)下(xia)充型和凝固，金(jin)属补(bu)缩效(xiao)果好(hao)，铸件外层组织致密，非金(jin)属夹杂(za)物(wu)少，机(ji)械(xie)性能好(hao)；不(bu)用(yong)造型、制芯，节省了(le)相关材料及设备投入。