輥(gun)列(lie)設計(ji)是(shi)(shi)(shi)影(ying)響鑄坯(pi)(pi)內(nei)部質(zhi)量的(de)(de)(de)(de)最重(zhong)要(yao)(yao)因素,不銹鋼連鑄機的(de)(de)(de)(de)鑄流導向段要(yao)(yao)求有更堅固(gu)(gu)的(de)(de)(de)(de)剛(gang)性,由(you)于鐵素體鋼在高(gao)溫時有高(gao)蠕變(bian)率,輥(gun)子(zi)的(de)(de)(de)(de)間(jian)(jian)距設計(ji)要(yao)(yao)比碳鋼更緊密。避免(mian)鑄坯(pi)(pi)內(nei)部裂(lie)紋和(he)(he)中(zhong)(zhong)心(xin)偏(pian)析(xi)要(yao)(yao)采取的(de)(de)(de)(de)措施主要(yao)(yao)包括:一是(shi)(shi)(shi)理論上采用連續彎曲(qu)和(he)(he)矯直技術(shu)比多點彎曲(qu)和(he)(he)矯直更能(neng)(neng)減(jian)少固(gu)(gu)液(ye)相界面(mian)和(he)(he)表面(mian)應變(bian),從而提高(gao)鑄坯(pi)(pi)的(de)(de)(de)(de)內(nei)部和(he)(he)表面(mian)質(zhi)量。二是(shi)(shi)(shi)采用小(xiao)(xiao)輥(gun)徑、分節輥(gun)并(bing)使輥(gun)子(zi)的(de)(de)(de)(de)中(zhong)(zhong)間(jian)(jian)支撐軸承座寬(kuan)度盡量小(xiao)(xiao),將(jiang)扇形段輥(gun)子(zi)的(de)(de)(de)(de)偏(pian)斜不對中(zhong)(zhong)減(jian)到最小(xiao)(xiao),以(yi)避免(mian)鼓肚引起的(de)(de)(de)(de)內(nei)部裂(lie)紋和(he)(he)中(zhong)(zhong)心(xin)偏(pian)析(xi)。三是(shi)(shi)(shi)在凝固(gu)(gu)末端固(gu)(gu)液(ye)相區采用輕壓下技術(shu)來減(jian)小(xiao)(xiao)中(zhong)(zhong)心(xin)偏(pian)析(xi)。而電磁攪(jiao)拌(ban)能(neng)(neng)使晶粒細化,減(jian)少柱狀晶,增加(jia)等軸晶;消(xiao)(xiao)除(chu)夾雜(za)物在鑄坯(pi)(pi)內(nei)弧(hu)的(de)(de)(de)(de)聚集(ji);改(gai)善鑄坯(pi)(pi)中(zhong)(zhong)心(xin)縮(suo)孔(kong);消(xiao)(xiao)除(chu)或減(jian)輕中(zhong)(zhong)心(xin)偏(pian)析(xi)。
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