镀(du)锌(xin)(xin)螺(luo)丝(si)是螺(luo)丝(si)中比较(jiao)常用(yong)的(de)(de)一类,它是一种以表面(mian)(mian)处(chu)理方(fang)式来命名的(de)(de)螺(luo)丝(si)紧固(gu)件,有镀(du)白(bai)(bai)锌(xin)(xin)、蓝(lan)白(bai)(bai)锌(xin)(xin)、彩(cai)锌(xin)(xin)等。虽(sui)然镀(du)锌(xin)(xin)螺(luo)丝(si)很常见,但里面(mian)(mian)门道(dao)却(que)不少(shao),下面(mian)(mian)为您详解一下关于(yu)镀(du)锌(xin)(xin)螺(luo)丝(si)通常的(de)(de)几(ji)种处(chu)理方(fang)法:
1、电镀锌螺丝
电镀锌(xin)螺丝(si)是(shi)螺丝(si)紧(jin)固件(jian)产(chan)品(pin)生(sheng)产(chan)制造中(zhong)最常见的一(yi)种(zhong)表面处理方(fang)法(fa)和工(gong)(gong)艺(yi)技术(shu)。电镀锌(xin)层是(shi)典型的阳(yang)极性镀层,主(zhu)要用(yong)于提高基材,也用(yong)于提高基材的防蚀性能。由于其(qi)镀层厚度薄,也应用(yong)于一(yi)般(ban)环(huan)境条(tiao)件(jian)下的表面防腐保护。电镀锌(xin)螺丝(si)表面处理方(fang)法(fa)和工(gong)(gong)艺(yi)技术(shu),成本低(di)(di),工(gong)(gong)艺(yi)稳定可靠,方(fang)便使用(yong)。但是(shi),极易产(chan)生(sheng)氢(qing)脆(cui)现象,所(suo)以电镀锌(xin)后应及(ji)时进行去氢(qing)处理。另(ling)外,耐酸(suan)碱性较(jiao)差,防腐时间短(duan),工(gong)(gong)艺(yi)环(huan)保性低(di)(di)。
2、粉末渗锌螺丝
粉(fen)(fen)末(mo)渗(shen)(shen)(shen)(shen)锌(xin)(xin)(xin)螺(luo)丝(si)是以浸(jin)(jin)锌(xin)(xin)(xin)剂为供(gong)锌(xin)(xin)(xin)源,通过加热产(chan)生锌(xin)(xin)(xin),铁原子互扩散而在(zai)钢(gang)铁表面(mian)性曾浸(jin)(jin)锌(xin)(xin)(xin)层(ceng)(ceng)(锌(xin)(xin)(xin)-铁合(he)金(jin)层(ceng)(ceng))得(de)表面(mian)处(chu)理(li)工艺(yi)(yi)。粉(fen)(fen)末(mo)渗(shen)(shen)(shen)(shen)锌(xin)(xin)(xin)的主(zhu)要成(cheng)分是纯锌(xin)(xin)(xin)粉(fen)(fen),其中(zhong)加入适(shi)量的填(tian)充(chong)材料(liao)如(ru)氧(yang)化铝,耐火(huo)土(tu)和(he)氯化铵(an)。粉(fen)(fen)末(mo)渗(shen)(shen)(shen)(shen)锌(xin)(xin)(xin)螺(luo)丝(si)最突(tu)出(chu)的特(te)点不是一种外(wai)附的镀(du)层(ceng)(ceng),而是基(ji)体(ti)金(jin)属与渗(shen)(shen)(shen)(shen)层(ceng)(ceng)构成(cheng)了有机(ji)的一体(ti),因(yin)而结合(he)非常牢(lao)固。粉(fen)(fen)末(mo)渗(shen)(shen)(shen)(shen)锌(xin)(xin)(xin)层(ceng)(ceng)的硬度和(he)耐蚀性远优于电(dian)镀(du)锌(xin)(xin)(xin)层(ceng)(ceng)。粉(fen)(fen)末(mo)渗(shen)(shen)(shen)(shen)锌(xin)(xin)(xin)最突(tu)出(chu)的特(te)点是渗(shen)(shen)(shen)(shen)层(ceng)(ceng)均匀,没(mei)有氨脆,几乎没(mei)有变(bian)形(xing)。特(te)别适(shi)合(he)于螺(luo)帽,螺(luo)栓等(deng)紧固件以及小(xiao)五金(jin)制(zhi)品,形(xing)状复杂(za)的工件和(he)粉(fen)(fen)末(mo)冶金(jin)产(chan)品的表面(mian)防腐处(chu)理(li)工艺(yi)(yi)。
3、机械镀锌螺丝
机械镀(du)锌(xin)(xin)(xin)螺丝是在锌(xin)(xin)(xin)粉及分散剂,促进(jin)剂,液体介(jie)质(zhi)等物质(zhi)存在的(de)(de)条件(jian)(jian)(jian)下,利用冲击(ji)介(jie)质(zhi),冲击(ji)碰撞(zhuang)钢铁(tie)制(zhi)件(jian)(jian)(jian)表(biao)(biao)面(mian),然后在制(zhi)件(jian)(jian)(jian)表(biao)(biao)面(mian)形成(cheng)镀(du)锌(xin)(xin)(xin)层(ceng)(ceng)(ceng)(ceng)的(de)(de)表(biao)(biao)面(mian)处理工艺。机械镀(du)锌(xin)(xin)(xin)层(ceng)(ceng)(ceng)(ceng)是与电(dian)镀(du)锌(xin)(xin)(xin),热镀(du)锌(xin)(xin)(xin)完全不(bu)(bu)同的(de)(de)工艺处理过程(cheng),它形成(cheng)的(de)(de)是一种防腐镀(du)层(ceng)(ceng)(ceng)(ceng)。其特(te)点:室(shi)温(wen)条件(jian)(jian)(jian)生产操作,通(tong)过装载零件(jian)(jian)(jian)镀(du)筒的(de)(de)旋转(zhuan),使筒内的(de)(de)冲击(ji)介(jie)质(zhi)随着滚筒的(de)(de)旋转(zhuan),和(he)零件(jian)(jian)(jian)相互碰撞(zhuang)产生机械冲击(ji)力,将锌(xin)(xin)(xin)粉碰撞(zhuang)沉(chen)积于制(zhi)件(jian)(jian)(jian)的(de)(de)表(biao)(biao)面(mian),从而(er)形成(cheng)具(ju)有金属锌(xin)(xin)(xin)基本物理特(te)征的(de)(de)镀(du)层(ceng)(ceng)(ceng)(ceng)。其缺(que)点:锌(xin)(xin)(xin)层(ceng)(ceng)(ceng)(ceng)厚度存在不(bu)(bu)均匀(yun)性;锌(xin)(xin)(xin)层(ceng)(ceng)(ceng)(ceng)不(bu)(bu)如电(dian)镀(du)层(ceng)(ceng)(ceng)(ceng)光滑,光亮。
4、热浸镀锌螺丝
热(re)(re)浸(jin)(jin)(jin)(jin)镀(du)(du)(du)(du)锌(xin)(xin)(xin)通常(chang)也(ye)称之为热(re)(re)镀(du)(du)(du)(du)锌(xin)(xin)(xin),热(re)(re)浸(jin)(jin)(jin)(jin)镀(du)(du)(du)(du)锌(xin)(xin)(xin)是将经过前期处理(li)的(de)钢铁(tie)制(zhi)件(jian)(jian)进入熔(rong)融的(de)锌(xin)(xin)(xin)液中,在其表(biao)面(mian)形成锌(xin)(xin)(xin)和(he)(he)(或(huo))锌(xin)(xin)(xin)-铁(tie)合(he)金镀(du)(du)(du)(du)层,从而获(huo)得金属覆盖(gai)层的(de)工(gong)艺过程和(he)(he)方法。热(re)(re)浸(jin)(jin)(jin)(jin)镀(du)(du)(du)(du)锌(xin)(xin)(xin)应用面(mian)极其广(guang)泛,如(ru)热(re)(re)浸(jin)(jin)(jin)(jin)镀(du)(du)(du)(du)锌(xin)(xin)(xin)高速公路交通隔栏(比如(ru)高速公路护(hu)栏紧(jin)固件(jian)(jian)连接紧(jin)固件(jian)(jian)等(deng)。热(re)(re)浸(jin)(jin)(jin)(jin)镀(du)(du)(du)(du)锌(xin)(xin)(xin)层特点(dian)是覆盖(gai)防(fang)护(hu)能力(li)好,对抗大(da)气腐(fu)蚀的(de)能力(li)优于电镀(du)(du)(du)(du)锌(xin)(xin)(xin)。