Thaum lub sij hawm tsim khoom, thaum cov yas yaj yog txhaj rau hauv pwm kab noj hniav nyob rau hauv qhov kub thiab txias thiab molded nyob rau hauv siab, thaum kub poob, lub yaj txias thiab solidifies rau hauv ib feem yas. Qhov luaj li cas ntawm cov yas yog me dua li ntawm cov pwm kab noj hniav, uas yog hu ua shorten. Lub ntsiab yog vim li cas rau shortening yog raws li nram no. Thaum ua cov yas, qhov sib txawv ntawm qhov sib txawv ntawm cov pwm rooj vag sib txawv. Lub rooj vag loj pab ua kom cov kab noj hniav siab, ncua lub sijhawm kaw ntawm lub rooj vag, thiab pab txhawb ntau yaj ntws mus rau hauv cov kab noj hniav, yog li qhov ntom ntawm cov yas kuj tseem ntau dua, yog li txo qhov luv luv, txwv tsis pub nws yuav ua rau kom luv luv. tus nqi.
Kev hloov pauv hauv cov qauv tshuaj ntawm cov yas pwm thaum lub sijhawm tsim khoom. Qee cov yas hloov lawv cov qauv tshuaj thaum lub sij hawm molding txheej txheem. Piv txwv li, hauv cov thermosetting plastics, cov resin molecule hloov los ntawm cov qauv linear mus rau lub cev zoo li cov qauv. Lub volumetric loj ntawm lub cev zoo li cov qauv yog ntau dua li ntawm cov qauv linear, yog li nws tag nrho cov ntim yog luv, ua rau shortening. Thin-walled yas qhov chaw nrog cov phab ntsa tuab yog txias sai dua hauv pwm kab noj hniav, thiab tus nqi luv luv yuav yog qhov tsawg tshaj plaws tom qab demolding. Lub sijhawm ntev dua rau cov yas tuab nrog tib phab ntsa tuab kom txias hauv cov kab noj hniav, qhov ntau dua qhov luv tom qab demolding. Yog hais tias lub thickness ntawm cov yas yog txawv, yuav muaj ib tug tej yam degree ntawm shortening tom qab demolding. Nyob rau hauv cov ntaub ntawv ntawm xws li ib tug tam sim ntawd hloov nyob rau hauv phab ntsa thickness, lub shortening tus nqi kuj yuav hloov dheev, ua rau muaj kev ntxhov siab nyob rau hauv ntau dua.
Residual stress pauv. Thaum cov khoom yas yog molded, vim lub zog ntawm molding siab thiab shear quab yuam, anisotropy, tsis sib npaug ntawm cov additives thiab pwm kub, muaj residual stresses nyob rau hauv molded yas qhov chaw, thiab cov residual stresses yuav maj mam ua me me thiab rov kis, ua rau cov khoom yas Qhov luv dua yog feem ntau hu ua post-shortening.
Post lub sij hawm: Lub Xya hli ntuj-19-2021