Xya Caw Txheem Kom Zoo Rau Hauv Kev Txhaj Tshuaj Molding

1. Daim ntawv thiab muab xam ntawm qhov ntsuas ntawm cov thermoplastics raws li tau hais los saum no. Cov xwm txheej cuam tshuam ntsim ntawm thermoplastics yog raws li nram no: 1.1 Thaum lub sijhawm ua cov txheej txheem ntawm thermoplastics, tseem muaj qee yam tseem ceeb xws li qhov hloov pauv ntawm crystallization, muaj zog sab hauv kev nyuaj siab, plawg residual stress frozen hauv cov yas, muaj zog molecular orientation thiab li. Yog li no, piv nrog cov thermosetting uas plastics, cov yam cuam tshuam rau shrinkage ntawm thermoplastics yog raws li nram no: 1. Lub shrinkage tus nqi yog loj dua, qhov sib txav ntau yog qhov dav thiab qhov orientation yog pom tseeb. Tsis tas li ntawd, qhov qis dua tom qab moulding, kev kho los yog kev ntub dej noo yog feem ntau loj tshaj qhov uas ntawm cov thermosetting plastics. 1.2 Lub txheej sab nrauv ntawm cov hlau uas hu ua cov kab tawm ntawm qhov kab noj hniav yog tam sim ntawd txias rau ib lub plhaub ntim khoom qis thaum lub sij hawm cov yam ntxwv ntawm cov khoom yas. Vim cov neeg txom nyem thermal conductivity ntawm plastics, lub puab txheej ntawm cov yas ntawm qhov chaw qeeb qeeb txias rau ib tug high-density khoom txheej nrog loj shrinkage. Li ntawd phab ntsa thickness, qeeb txias thiab siab ceev txheej txheej thickness shrink zoo heev. Tsis tas li ntawd, qhov teeb tsa thiab qhov ntau ntawm cov qhov siv thiab cov ntawv ntim muaj feem xyuam ncaj nraim rau ntawm cov khoom siv khiav ceev, qhov sib npaug thiab kev sib zog ua haujlwm, yog li cov yam ntxwv ntawm cov khoom yas tau muaj feem cuam tshuam loj dua thiab cov kev taw qhia. 1.3 Daim ntawv, qhov loj me thiab kev faib tawm ntawm txoj hlua thiab qhov hluav taws xob ncaj qha cuam tshuam rau cov khoom siv khiav ceev, qhov sib npaug, kev ceev thiab kev noj cov nyom thiab kev tsim lub sijhawm. Kev sib tw loj (qhov tshwj xeeb tshaj yog qhov sib npaug ntawm qhov sib tshooj) ntawm txoj kev ncaj qha thiab kev nkag hauv qab muaj qhov qis dua, tiam sis muaj qhov loj tshaj, thaum lub dav thiab qhov ntev ntawm qhov nkag thiab qhov hluav taws xob muaj me me. Kaw rau hauv kev nkag mus los yog mus ncaj nraim mus rau kev coj ua ntawm cov khoom siv, qhov ntswg yog loj.