熱處理對于有高硬度、高耐磨性和高韌性要求的塑料模具，表面熱處理廠家要選用滲碳鋼來制造，并把滲碳、淬火和低溫回火作為最終熱處理，表面熱處理廠家對滲(shen)碳(tan)(tan)層(ceng)(ceng)(ceng)的(de)要求，一般滲(shen)碳(tan)(tan)層(ceng)(ceng)(ceng)的(de)厚(hou)度為(wei)o．8—1．5mm，當壓制(zhi)含(han)硬質填料(liao)的(de)塑料(liao)時(shi)，模具滲(shen)碳(tan)(tan)層(ceng)(ceng)(ceng)厚(hou)度要求為(wei)1．3~15mm，壓制(zhi)軟(ruan)性(xing)(xing)塑料(liao)時(shi)滲(shen)碳(tan)(tan)層(ceng)(ceng)(ceng)厚(hou)度為(wei)0.8~1．2mm。滲(shen)碳(tan)(tan)層(ceng)(ceng)(ceng)的(de)碳(tan)(tan)含(han)量為(wei)0.7％~1.0％為(wei)佳。若采用碳(tan)(tan)氮共滲(shen)，則耐磨性(xing)(xing)、耐腐蝕(shi)性(xing)(xing)、抗(kang)氧(yang)化、防粘性(xing)(xing)就更好。

滲碳(tan)溫(wen)度(du)一般在900—920攝(she)氏度(du)之間(jian)，復(fu)雜型(xing)腔的(de)小型(xing)模具（模具鋼(gang)）可取(qu)840—860攝(she)氏度(du)中(zhong)(zhong)溫(wen)碳(tan)氮共滲。滲碳(tan)保溫(wen)時(shi)間(jian)為1~l0h．具體應根據對滲層(ceng)厚(hou)度(du)的(de)要求(qiu)來(lai)選擇。滲碳(tan)工(gong)藝以采用分級(ji)滲碳(tan)工(gong)藝為宜，即高溫(wen)階段(900—920攝(she)氏度(du))以快速將碳(tan)滲入(ru)零件表層(ceng)為主(zhu)．中(zhong)(zhong)溫(wen)階段(820~840攝(she)氏度(du))以增加(jia)滲碳(tan)層(ceng)厚(hou)度(du)為主(zhu)，這樣(yang)在滲碳(tan)層(ceng)內(nei)建立均勻合理的(de)碳(tan)濃(nong)度(du)梯度(du)分布，便于直接(jie)淬(cui)火(huo)。

提高(gao)韌性(xing)(xing)的(de)球(qiu)墨(mo)(mo)鑄(zhu)(zhu)(zhu)(zhu)鐵(tie)(tie)退火(huo)球(qiu)墨(mo)(mo)鑄(zhu)(zhu)(zhu)(zhu)鐵(tie)(tie)在鑄(zhu)(zhu)(zhu)(zhu)造過程中此普通灰(hui)口鑄(zhu)(zhu)(zhu)(zhu)鐵(tie)(tie)的(de)白口傾(qing)向大，內應力也較大，鑄(zhu)(zhu)(zhu)(zhu)鐵(tie)(tie)件(jian)(jian)(jian)很難得到純粹的(de)鐵(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)或(huo)(huo)珠(zhu)(zhu)光(guang)(guang)體(ti)(ti)(ti)(ti)(ti)基體(ti)(ti)(ti)(ti)(ti)，為(wei)(wei)(wei)(wei)提高(gao)鑄(zhu)(zhu)(zhu)(zhu)鐵(tie)(tie)件(jian)(jian)(jian)的(de)延(yan)性(xing)(xing)或(huo)(huo)韌性(xing)(xing)，常將(jiang)(jiang)鑄(zhu)(zhu)(zhu)(zhu)鐵(tie)(tie)件(jian)(jian)(jian)重(zhong)新加(jia)熱(re)到900-950℃并(bing)保(bao)溫(wen)(wen)足夠時間進行高(gao)溫(wen)(wen)退火(huo)，再爐(lu)冷(leng)(leng)到600℃出(chu)爐(lu)變(bian)冷(leng)(leng)。若(ruo)鑄(zhu)(zhu)(zhu)(zhu)態組織由(鐵(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)＋珠(zhu)(zhu)光(guang)(guang)體(ti)(ti)(ti)(ti)(ti))基體(ti)(ti)(ti)(ti)(ti)，以及(ji)球(qiu)狀(zhuang)石墨(mo)(mo)組成，為(wei)(wei)(wei)(wei)提高(gao)韌性(xing)(xing)，只需將(jiang)(jiang)珠(zhu)(zhu)光(guang)(guang)體(ti)(ti)(ti)(ti)(ti)中滲碳(tan)體(ti)(ti)(ti)(ti)(ti)分(fen)解(jie)轉換為(wei)(wei)(wei)(wei)鐵(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)及(ji)球(qiu)狀(zhuang)石墨(mo)(mo)，為(wei)(wei)(wei)(wei)此將(jiang)(jiang)鑄(zhu)(zhu)(zhu)(zhu)鐵(tie)(tie)件(jian)(jian)(jian)重(zhong)新加(jia)熱(re)到700-760℃的(de)共析溫(wen)(wen)度上下經保(bao)溫(wen)(wen)后爐(lu)冷(leng)(leng)至600℃出(chu)爐(lu)變(bian)冷(leng)(leng)。工藝過程是將(jiang)(jiang)基體(ti)(ti)(ti)(ti)(ti)為(wei)(wei)(wei)(wei)鐵(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)及(ji)珠(zhu)(zhu)光(guang)(guang)體(ti)(ti)(ti)(ti)(ti)的(de)球(qiu)墨(mo)(mo)鑄(zhu)(zhu)(zhu)(zhu)鐵(tie)(tie)件(jian)(jian)(jian)重(zhong)新加(jia)熱(re)到850-900℃溫(wen)(wen)度，原鐵(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)及(ji)珠(zhu)(zhu)光(guang)(guang)體(ti)(ti)(ti)(ti)(ti)轉換為(wei)(wei)(wei)(wei)奧氏(shi)體(ti)(ti)(ti)(ti)(ti)，并(bing)有(you)部(bu)分(fen)球(qiu)狀(zhuang)石墨(mo)(mo)溶(rong)解(jie)于奧氏(shi)體(ti)(ti)(ti)(ti)(ti)，經保(bao)溫(wen)(wen)后空冷(leng)(leng)奧氏(shi)體(ti)(ti)(ti)(ti)(ti)轉變(bian)為(wei)(wei)(wei)(wei)細珠(zhu)(zhu)光(guang)(guang)體(ti)(ti)(ti)(ti)(ti)，因此鑄(zhu)(zhu)(zhu)(zhu)件(jian)(jian)(jian)的(de)強度提高(gao)。