增碳(tan)(tan)剂,顾名思义,主要的(de)成(cheng)分(fen)(fen)就(jiu)是(shi)碳(tan)(tan),作用就(jiu)是(shi)增碳(tan)(tan),但是(shi)不(bu)同(tong)增碳(tan)(tan)剂的(de)品质(zhi)(zhi)也不(bu)尽相同(tong),比如说有:石(shi)墨(mo)基的(de)、煅烧(shao)石(shi)油焦基的(de),煅煤(mei)的(de)、废旧(jiu)电(dian)极碎的(de)、颗粒再造的(de)等等,主要成(cheng)分(fen)(fen)是(shi)碳(tan)(tan),很(hen)肯定,含(han)碳(tan)(tan)量(liang)(liang)(liang)(liang)越高,基本杂(za)质(zhi)(zhi)就(jiu)越低(基本杂(za)质(zhi)(zhi)泛(fan)指灰分(fen)(fen),挥发(fa)分(fen)(fen)等)再一(yi)个就(jiu)是(shi)成(cheng)分(fen)(fen)中的(de)硫氮(dan)(dan)含(han)量(liang)(liang)(liang)(liang),硫的(de)作用大家基本比较(jiao)清晰,在铸(zhu)铁中含(han)有硫分(fen)(fen)能(neng)够好的(de)提高铸(zhu)件的(de)物理性能(neng),这几(ji)年氮(dan)(dan)含(han)量(liang)(liang)(liang)(liang)也被大家广泛(fan)研究,氮(dan)(dan)含(han)量(liang)(liang)(liang)(liang)太(tai)高,产生氮(dan)(dan)气孔,氮(dan)(dan)含(han)量(liang)(liang)(liang)(liang)过低,铸(zhu)件的(de)硬度上不(bu)去(qu),铁素(su)体(ti)多,一(yi)般来说铁水(shui)的(de)氮(dan)(dan)含(han)量(liang)(liang)(liang)(liang)控制在80ppm之间。

增碳剂的原料有很多种,生产工艺也各异,有木质碳类,煤质碳类,焦炭类,石墨类等,其中各种分类下又有很多小种类。增碳剂一般指经过石墨化的增碳剂,在高温条件下,碳原子的排列呈石墨的微观形态,所以称之为石墨化。
增(zeng)碳(tan)(tan)剂(ji)厂家会(hui)利用(yong)石(shi)墨化工艺降(jiang)低增(zeng)碳(tan)(tan)剂(ji)中杂质的(de)(de)含(han)量(liang),提高增(zeng)碳(tan)(tan)剂(ji)的(de)(de)碳(tan)(tan)含(han)量(liang),降(jiang)低硫含(han)量(liang)。增(zeng)碳(tan)(tan)剂(ji)在铸造时使用(yong),可大幅(fu)度增(zeng)加废钢用(yong)量(liang),减少生铁(tie)(tie)用(yong)量(liang)或不用(yong)生铁(tie)(tie)。

电炉熔炼的投料方式,应将增碳剂随废钢等炉料一起往里投放,小剂量的添加可以选择加在铁水表面。但是要避免大批量往铁水里投料,以防止氧化过多而出现增碳效果不明显和铸件碳含量不够的情况。增碳剂的加入量,根据其他原材料的配比和含碳量来定。
不同(tong)种类的(de)铸铁(tie)(tie),根据需要选(xuan)择(ze)不同(tong)型号的(de)增(zeng)碳剂。增(zeng)碳剂特点本(ben)身选(xuan)择(ze)纯净的(de)含碳石墨化物质(zhi),降(jiang)低生铁(tie)(tie)里过(guo)多的(de)杂质(zhi),增(zeng)碳剂选(xuan)择(ze)合适可(ke)降(jiang)低铸件生产成本(ben)。

增碳(tan)(tan)(tan)剂(ji)适(shi)于(yu)在(zai)感应炉中(zhong)(zhong)(zhong)熔(rong)(rong)(rong)(rong)炼使(shi)用(yong),但依据工艺(yi)要求(qiu)具体使(shi)用(yong)也不(bu)(bu)尽相同。在(zai)中(zhong)(zhong)(zhong)频电(dian)炉熔(rong)(rong)(rong)(rong)炼中(zhong)(zhong)(zhong)使(shi)用(yong)增碳(tan)(tan)(tan)剂(ji),可按配比或(huo)碳(tan)(tan)(tan)当(dang)量要求(qiu)随料(liao)(liao)加入(ru)(ru)电(dian)炉中(zhong)(zhong)(zhong)下部(bu)位,回收率可达95%以(yi)(yi)上(shang);如果(guo)碳(tan)(tan)(tan)量不(bu)(bu)足调整碳(tan)(tan)(tan)分时(shi),先打净炉中(zhong)(zhong)(zhong)熔(rong)(rong)(rong)(rong)渣,再加增碳(tan)(tan)(tan)剂(ji),通过铁液(ye)(ye)升温(wen),电(dian)磁(ci)搅拌(ban)或(huo)人(ren)工搅拌(ban)使(shi)碳(tan)(tan)(tan)溶解吸收,回收率可在(zai)90%左(zuo)右,如果(guo)采用(yong)低(di)温(wen)增碳(tan)(tan)(tan)工艺(yi),即炉料(liao)(liao)只熔(rong)(rong)(rong)(rong)化一(yi)部(bu)分,熔(rong)(rong)(rong)(rong)化的铁液(ye)(ye)温(wen)度较低(di)的情况下,全部(bu)增碳(tan)(tan)(tan)剂(ji)一(yi)次性加入(ru)(ru)铁液(ye)(ye)中(zhong)(zhong)(zhong),同时(shi)用(yong)固体炉料(liao)(liao)将其压入(ru)(ru)铁液(ye)(ye)中(zhong)(zhong)(zhong)不(bu)(bu)让其露出铁液(ye)(ye)表(biao)面。这(zhei)种方(fang)法铁液(ye)(ye)增碳(tan)(tan)(tan)可达1.0%以(yi)(yi)上(shang)。