咨询热线:

0531-88771136

您的当前位置: 首页 > 新闻中心 > 正文

灰铸铁浇注温度过低是怎么回事?

来源:http://www.jnhjgs.cn     发布时间:2021-11-17 17:14:34    点击:

硫化锰气孔
Manganese sulfide pore
缺陷产生原因:此种气孔位于灰铸铁件表皮以下且多在上面,常在加工后显露出来,气孔直径约2~6mm。有时孔中含有少量熔渣,金相研究表明,此缺陷是由MnS偏析与熔渣混合而成,原因是浇注温度低,同时铁液中含Mn和S量高。
Causes of defects: such pores are located below and mostly on the surface of gray iron castings, and are often exposed after processing. The diameter of pores is about 2 ~ 6mm. Sometimes there is a small amount of slag in the hole. Metallographic study shows that this defect is caused by the mixture of MNS segregation and slag. The reason is that the pouring temperature is low and the content of Mn and s in molten iron is high.
解决办法:这样的含S量和适宜的含Mn量(0.5%~0.65%),可以显著改善铁液纯度,从而有效地防止这类缺陷。
Solution: such s content and appropriate Mn content (0.5% ~ 0.65%) can significantly improve the purity of molten iron, so as to effectively prevent such defects.
砂芯气体引起的气孔
Porosity caused by core gas
缺陷产生原因:气孔和多空性气孔常因砂芯排气不良而引起。因为造芯时砂芯多在芯盒中硬化,这就常使砂芯排气孔数量不够。
Causes of defects: pores and porous pores are often caused by poor exhaust of sand core. Because the sand core is mostly hardened in the core box during core making, the number of exhaust holes of the sand core is often insufficient.
解决办法:为了形成排气孔,可在型芯硬化后补充钻孔。
Solution: in order to form an exhaust hole, add drilling after the core is hardened.
山东铝合金压铸
液体夹渣
Liquid slag inclusion
缺陷产生原因:值得一提的是改变浇注系统设计,未能消除此缺陷,故此种缺陷可以认为是由于浇注温度低以及铁液在微量还原气氛下浇注时形成的。加工后灰铸铁件表皮之下会发现一个个单体的小孔,孔的直径一般为1~3mm。个别情况下只有1~2个小孔。金相研究表明,这些小孔与少量的液体夹渣一起出现,但该处未发现S的偏析。
Causes of defects: it is worth mentioning that changing the gating system design failed to eliminate this defect, so this defect can be considered to be formed due to low pouring temperature and molten iron pouring in micro reducing atmosphere. After processing, individual small holes will be found under the skin of gray iron castings, and the diameter of the holes is generally 1 ~ 3mm. In some cases, there are only 1 ~ 2 small holes. Metallographic study shows that these small holes appear together with a small amount of liquid slag inclusion, but there is no segregation of S.
解决办法:研究表明,这种缺陷与浇注温度有关,浇注温度高于1380℃时,铸件中未发现这种缺陷,故浇注温度应控制在1380~1420℃。
Solution: the research shows that this defect is related to the pouring temperature. When the pouring temperature is higher than 1380 ℃, this defect is not found in the casting, so the pouring temperature should be controlled at 1380 ~ 1420 ℃.
联系我们 contact

山东济南模具_铝合金压铸厂-山东宏捷模具有限公司

电话1:13173017488

电话2:18615459955

传真:0531-88771136

邮箱:hlm369@126.com

地址:山东省济南市大桥镇大王村北跨商务中心后三层白楼

山东济南模具_铝合金压铸厂-山东宏捷模具有限公司 手机: 13173017488 咨询热线: 0531-88771136 咨询热线:18615459955    邮箱:hlm369@126.com

公司地址: 山东省济南市大桥镇大王村北跨商务中心后三层白楼