我厂以0.5吨电弧炉,熔炼合金铸铁活塞环。铸型的砂箱,用铝合金制成。在浇注中,因铁水跑火,经常将砂箱,冲熔成铝块和铝粒,混入炉料。同时,跑箱流出铁水,凝固后,表面附着铝层。这些铝或含铝铁料,加入炉内熔炼,将产生程度不同的皮下气孔。特别是浇注截面小的环体,更为严重。过去,我们对含铝铁水,产生的活塞环皮下气孔。束手无策,只能将整炉铁水倒掉。而且,倒掉铁水,再不能用作炉料,造成极大浪费。后来,据有关资料介绍,“稀土合金有去气作用”的记载,经多次操作试验,确认含铝铁水所铸活塞环皮下气孔,可以用稀土合金作处理剂加以消除。我们以∑Re-24稀土合金作处理剂,先消除皮下气孔。再经提温和调整断面结构。得到既无气孔,金相组织合格的活塞环。例如81年113炉次,在熔炼CA-10平环时,因加入合铝炉料,在出炉前的三角试片上有气孔。经试浇,在环体90°截面表皮下,有严重气孔。(内园较外园严重)处理方法:抓除渣子,加入稀土块5公斤、(每块1-1.5公斤为宜)关闭炉门、停电5分钟;此时,稀土块即在铁水表面轻轻沸腾,而且游动。稀土熔化后,搅拌铁水、浇三角试片、断面无气孔。接着,加C粉约一公斤,提温10门分钟,试浇一垛活塞环,在环体90°截面向园仍有轻微气孔。再经上述处理,加三公斤稀土块,5分钟后,环体气孔完全消 I plant to 0.5 tons arc furnace, alloy cast iron piston ring. Mold flask, made of aluminum alloy. In the pouring, run hot because of hot metal, often sand box, red melt into aluminum and aluminum particles, mixed with charge. Meanwhile, the running box out of hot metal, solidified, the surface attached to the aluminum layer. These aluminum or aluminum-containing iron, added to the furnace melting, will produce different degrees of subcutaneous pores. In particular, casting a small cross-section of the ring, more serious. In the past, we produced submerged holes in the piston rings of aluminum-containing hot metal. Helpless, only pour the entire furnace hot metal. Moreover, pouring hot metal, can not be used as a charge, resulting in tremendous waste. Later, according to relevant information, “Rare Earth Alloy has degassing effect” records, after many operation tests to confirm the aluminum-containing molten iron cast piston ring subcutaneous pores, rare earth alloys can be used as a treatment agent to be eliminated. We take ΣRe-24 rare earth alloy as a treatment agent, first to eliminate subcutaneous pores. Then by heating and adjusting the cross-section structure. Get both no porosity, metallurgical organization of the piston ring. For example, 113 times in 81 years, CA-10 flat ring in the smelting, due to join the aluminum charge, in the baked triangular test strips have pores. After pouring test, in the ring body 90 ° section under the skin, there are serious stomata. (The garden is more serious than the outer garden) Treatment: Grasping slag, add 5 kg of rare earth, (1-1.5 kg each appropriate) Turn off the door, power cut 5 minutes; At this time, the rare earth block that is mild in the molten iron surface Boiling, but also swimming. Rare earth melts, stirring hot metal, pouring triangular test piece, no pores in the section. Then, add about 1 kg of C powder, heat 10 minutes, pouring a pile of piston rings, the ring body 90 ° cross section to the park is still slightly stomatal. After the above treatment, plus three kilograms of rare earth blocks, 5 minutes later, the ring stoma completely eliminated