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)(shen)碳(tan)(tan)層的(de)(de)要求(qiu)，一般(ban)滲(shen)(shen)碳(tan)(tan)層的(de)(de)厚(hou)度(du)為o．8—1．5mm，當(dang)壓制(zhi)含硬質填料的(de)(de)塑料時(shi)，模具滲(shen)(shen)碳(tan)(tan)層厚(hou)度(du)要求(qiu)為1．3~15mm，壓制(zhi)軟性塑料時(shi)滲(shen)(shen)碳(tan)(tan)層厚(hou)度(du)為0.8~1．2mm。滲(shen)(shen)碳(tan)(tan)層的(de)(de)碳(tan)(tan)含量為0.7％~1.0％為佳。若采用碳(tan)(tan)氮共滲(shen)(shen)，則耐磨性、耐腐(fu)蝕(shi)性、抗(kang)氧化、防粘性就(jiu)更好。

滲(shen)(shen)(shen)碳(tan)(tan)溫(wen)(wen)度(du)(du)(du)(du)一般在(zai)900—920攝(she)氏度(du)(du)(du)(du)之間，復雜型(xing)腔(qiang)的小(xiao)型(xing)模具(ju)(ju)（模具(ju)(ju)鋼）可(ke)取840—860攝(she)氏度(du)(du)(du)(du)中(zhong)溫(wen)(wen)碳(tan)(tan)氮(dan)共滲(shen)(shen)(shen)。滲(shen)(shen)(shen)碳(tan)(tan)保(bao)溫(wen)(wen)時間為(wei)1~l0h．具(ju)(ju)體應根據(ju)對滲(shen)(shen)(shen)層厚度(du)(du)(du)(du)的要求來(lai)選擇(ze)。滲(shen)(shen)(shen)碳(tan)(tan)工藝以采用分(fen)級滲(shen)(shen)(shen)碳(tan)(tan)工藝為(wei)宜，即(ji)高溫(wen)(wen)階段(900—920攝(she)氏度(du)(du)(du)(du))以快速將碳(tan)(tan)滲(shen)(shen)(shen)入零件(jian)表層為(wei)主．中(zhong)溫(wen)(wen)階段(820~840攝(she)氏度(du)(du)(du)(du))以增加滲(shen)(shen)(shen)碳(tan)(tan)層厚度(du)(du)(du)(du)為(wei)主，這樣在(zai)滲(shen)(shen)(shen)碳(tan)(tan)層內建(jian)立均勻合理的碳(tan)(tan)濃度(du)(du)(du)(du)梯度(du)(du)(du)(du)分(fen)布，便(bian)于直接淬火。

提(ti)高(gao)(gao)韌性(xing)的球(qiu)墨鑄(zhu)鐵(tie)(tie)(tie)退火球(qiu)墨鑄(zhu)鐵(tie)(tie)(tie)在鑄(zhu)造過程(cheng)中(zhong)此(ci)普(pu)通灰口鑄(zhu)鐵(tie)(tie)(tie)的白口傾向大，內應力也較大，鑄(zhu)鐵(tie)(tie)(tie)件(jian)(jian)(jian)很難得到(dao)(dao)(dao)純粹的鐵(tie)(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)(ti)或珠(zhu)光(guang)體(ti)(ti)(ti)(ti)(ti)(ti)基(ji)(ji)體(ti)(ti)(ti)(ti)(ti)(ti)，為(wei)(wei)(wei)提(ti)高(gao)(gao)鑄(zhu)鐵(tie)(tie)(tie)件(jian)(jian)(jian)的延性(xing)或韌性(xing)，常(chang)將(jiang)(jiang)鑄(zhu)鐵(tie)(tie)(tie)件(jian)(jian)(jian)重新加熱(re)到(dao)(dao)(dao)900-950℃并(bing)保溫(wen)足夠時間(jian)進行高(gao)(gao)溫(wen)退火，再(zai)爐(lu)冷到(dao)(dao)(dao)600℃出爐(lu)變(bian)冷。若鑄(zhu)態組(zu)(zu)織(zhi)由(鐵(tie)(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)(ti)＋珠(zhu)光(guang)體(ti)(ti)(ti)(ti)(ti)(ti))基(ji)(ji)體(ti)(ti)(ti)(ti)(ti)(ti)，以及(ji)(ji)球(qiu)狀石(shi)墨組(zu)(zu)成，為(wei)(wei)(wei)提(ti)高(gao)(gao)韌性(xing)，只需將(jiang)(jiang)珠(zhu)光(guang)體(ti)(ti)(ti)(ti)(ti)(ti)中(zhong)滲碳體(ti)(ti)(ti)(ti)(ti)(ti)分解轉換為(wei)(wei)(wei)鐵(tie)(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)(ti)及(ji)(ji)球(qiu)狀石(shi)墨，為(wei)(wei)(wei)此(ci)將(jiang)(jiang)鑄(zhu)鐵(tie)(tie)(tie)件(jian)(jian)(jian)重新加熱(re)到(dao)(dao)(dao)700-760℃的共析溫(wen)度(du)上下經(jing)保溫(wen)后(hou)爐(lu)冷至600℃出爐(lu)變(bian)冷。工藝過程(cheng)是(shi)將(jiang)(jiang)基(ji)(ji)體(ti)(ti)(ti)(ti)(ti)(ti)為(wei)(wei)(wei)鐵(tie)(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)(ti)及(ji)(ji)珠(zhu)光(guang)體(ti)(ti)(ti)(ti)(ti)(ti)的球(qiu)墨鑄(zhu)鐵(tie)(tie)(tie)件(jian)(jian)(jian)重新加熱(re)到(dao)(dao)(dao)850-900℃溫(wen)度(du)，原鐵(tie)(tie)(tie)素(su)體(ti)(ti)(ti)(ti)(ti)(ti)及(ji)(ji)珠(zhu)光(guang)體(ti)(ti)(ti)(ti)(ti)(ti)轉換為(wei)(wei)(wei)奧(ao)(ao)氏(shi)(shi)體(ti)(ti)(ti)(ti)(ti)(ti)，并(bing)有部(bu)分球(qiu)狀石(shi)墨溶解于(yu)奧(ao)(ao)氏(shi)(shi)體(ti)(ti)(ti)(ti)(ti)(ti)，經(jing)保溫(wen)后(hou)空冷奧(ao)(ao)氏(shi)(shi)體(ti)(ti)(ti)(ti)(ti)(ti)轉變(bian)為(wei)(wei)(wei)細珠(zhu)光(guang)體(ti)(ti)(ti)(ti)(ti)(ti)，因此(ci)鑄(zhu)件(jian)(jian)(jian)的強度(du)提(ti)高(gao)(gao)。