【摘要】 方坯连铸机浇铸的高碳钢坯,其深加工产品是机械性能要求较高的钢丝绳、预应力钢丝、轮胎钢丝及弹簧钢丝等。钢中脆性、大颗料夹杂物是工艺过程的脱氧产物;高碳钢铸坯凝固过程中产生严重的中心偏析和中心疏松缺陷。这些夹杂物和缺陷使得钢丝在冷拔过程中或在使用过程中出现非疲劳断丝。避免质量事故的方法是:控制高碳钢钢水的质量,将炼钢脱氧过程产生Al2O3脆性氧化物夹杂,通过控制渣系使生成的MnO2-Al2O3-SiO2系三元夹杂分布在低熔点区;必须实现无氧化保护浇注;中间包内腔优化对夹杂物上浮效果显著;保证工艺过程操作的最小温度降低;采用连铸坯轻压下技术或高强度高密度冷却技术、结晶器电磁搅拌和控制冷却强度。更多还原

【Abstract】 Continuous cast high0carbon steel billets are used to make such deep-processed products as wire ropes,prestressed rods,tyre wires and spring wires,for which high mechanical properties are required.It was found that such microstructural defects as severe centerline segregation and central porosity often occurred in the ingots,and large-sized,brittle nonmetallic inclusions formed form the deoxidization process.It was these defects that caused non-fatigue failure of the wires during cold drawing or in service.The following measures ard thus proposed to prevent these defects.The moltensteel is purified by forming a low-melting point ternary slag system MnO2-Al2O3-SiO2,so as to remove the brittle inclusions Al2O3;a protective,oxidation-free casting procedure is employed;the tundish design is optimized to facilitate the slag floating; a minimum temperature drop during casting is ensured.Meanwhile,such manufacturing techniques as slight reducation and/or strong cooling of the billets,as well as electromagnetic agitation and controlled cooling of the molds,are also found to be elimination of these defects.更多还原