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★★★★★★★★無錫潤瀛鋼鐵有限公司★★★★★★★★       聯(lián)系人：小何  電話：0510-81814456   18961719789   QQ：2678848969                                                                                           
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
                                                                                       無錫潤瀛鋼鐵有限公司，公司占地面積9000平方，是無錫市特鋼行業(yè)中的大型銷售企業(yè)。依托江蘇無錫的有利經(jīng)濟環(huán)境，產(chǎn)品主要面向國內各大城市及港澳臺地區(qū)，公司庫存常年保持萬噸以上.是中國長江以北,鋼材品種最全、銷售各種圓鋼.代理國內外知名品牌：寶鋼、東北特鋼、首鋼、扶鋼、興澄特鋼，日本新日鐵、德國蒂森克虜伯的產(chǎn)品。為更好的服務客戶擴大經(jīng)營范圍，我公司特開辦了上門送貨服務，并有專車專人接送洽談人員前來訂購業(yè)務，是銷售與配送為一體的綜合性企業(yè).                                                                                                                              

產(chǎn)品符合非標，國標，德標，日標，美標，軍工，以一流的品質，服務國內各大知名企業(yè)，以優(yōu)秀的管理理念打造中國鋼鐵的新未來                                                                                                                              

                                                                                                                                ★合金結構鋼一般分為調質結構鋼和表面硬化結構鋼。                                                                                                                                                                                                                                                                                                                                                                                                ①調質結構鋼                                                                                                                                這類鋼的含碳量一般約為0.25％～0.55％，對于既定截面尺寸的結構件，在調質處理（淬火加回火）時，如果沿截面淬透，則力學性能良好，如果淬不透，顯微組織中出現(xiàn)有自由鐵素體，則韌性下降。對具有回火脆性傾向的鋼如錳鋼、鉻鋼、鎳鉻鋼等，回火后應快冷。這類鋼的淬火臨界直徑，隨晶粒度和合金元素含量的增加而增大，例如，40Cr和35SiMn鋼約為30～40mm，而40CrNiMo和30CrNi2MoV鋼則約為                                                                                                                                60～100mm，常用于制造承受較大載荷的軸、連桿等結構件。                                                                                                                                                                                                                                                                                                                                                                                                ②表面硬化結構鋼                                                                                                                                用以制造表層堅硬耐磨而心部柔韌的零部件,如齒輪、軸等。為使零件心部韌性高,鋼中含碳量應低，一般在0.12～0.25％，同時還有適量的合金元素，以保證適宜的淬透性。氮化鋼還需加入易形成氮化物的合金元素（如Al、Cr、Mo等）。滲碳或碳氮共滲鋼，經(jīng)850～950℃滲碳或碳氮共滲后，淬火并在低溫回火(約200℃)狀態(tài)下使用。氮化鋼經(jīng)氮化處理(480～580℃)，直接使用，不再經(jīng)淬火與回火處理。