论文部分内容阅读
The attempt to forecast the coming challenges for special melting technologies especially the ESR with liquid metal is presented.The overview on the development trends of ESR and related technologies with the focus on solidification control and economic efficiency is made.It is shown that due to gradual and quite slow formation both liquation development and top discard in ESR ingots is several times less comparing with usual heavy ingots.Much higher metal yield at high quality of the large ingots melted by ESR with consumable electrodes is the reason of the boom of ESR furnaces occurs last decade.Sufficient broaden of solidification control at ESR and,as consequence,improvement of ingots quality became possible due to application of current supplying mould (CSM).New ESR technologies (ESR TC,ESR LM) using CSM give good opportunities to control of liquid metal bath depth that allows to lower segregation processes development at solidification and to receive sound heavy ingots from steels and alloys are sensitive to segregation.In the process of Electroslag remelting (surfacing) by liquid metal ( ESR/ESS) LM) metal overheat is minimized.The investigation ESR/ESS LM ingots quality had shown very dense macrostructure with very low quantity of nonmetal inclusion,full absence of shrinkage defects and minimal liquation manifestations.ESR LM is one and only process is able to produce on one furnace very wide assortment: solid and hollow ingots,rolling mill bimetallic rolls and different other unique bimetal billets ( having as coaxial ( bimetallic rebar,rolls etc.) as diametric consequential ( turbine rotors etc ) layers).The absence of consumable electrodes ( neither manufacture and delivery,nor preparation and fastening) is unconditional advantage of electroslag technologies with liquid metal.Direct pouring of liquid metal reduces both furnaces height and production cost.It is shown that ESS LM is prospective for manufacture of big hollows billet for heavy pipes and various shells ring rolling,high speed rail road wheels,combined rotors for power generation,working and backup rolling mill rolls etc.