Cov qauv steel workpiece nyob rau hauv cov cua kub thiab txias txheej txheem, vim inconsistencies cua txias npaum li cas ntawm cov nto txheej thiab cov tub ntxhais seem thiab lub sij hawm tsim ib tug kub qhov sib txawv, nws yuav ua rau lub ntim expansion thiab contraction ntawm tsis sib xws kev nyuaj siab uas lub tshav kub kev nyuaj siab. Nyob rau hauv lub thermal kev nyuaj siab vim ib tug kub hauv qab ntawm qhov chaw pib mus rau hauv lub tub ntxhais seem, qhov contraction kuj tseem ntau dua li tawm hauv lub hauv paus core seem seem ntawm nro, thaum kawg ntawm qhov txias, txij li qhov chaw nruab nrab ntawm qhov kawg txias ntim contraction tsis tuaj yeem. ywj siab tawm ntawm qhov chaw nruab nrab ntawm qhov chaw siab nro. Uas yog nyob rau hauv tus ntawm thermal stress thaum kawg lub workpiece nto siab thiab lub plawv Ministry nro. Qhov tshwm sim no yog txias tshaj tawm, cov khoom muaj pes tsawg leeg thiab kev kho cua sov thiab lwm yam. Thaum txias, qhov nrawm dua, qhov siab dua cov ntsiab lus carbon thiab alloy muaj pes tsawg leeg, cov txheej txheem tsis sib xws ntawm cov yas deformation nyob rau hauv thermal stress generated los ntawm ntau dua, qhov kawg daim ntawv ntawm residual stress nws tau txais.

Ntawm qhov tod tes, cov hlau thaum kho cua sov vim yog qhov hloov pauv ntawm cov ntaub so ntswg xws li austenite rau martensite, nrog rau qhov nce ntawm qhov tshwj xeeb ntim ntawm lub ntim nthuav dav ntawm lub workpiece, ntau qhov chaw ntawm lub workpiece muaj ib theem hloov, uas ua rau inconsistency. ntawm qhov ntim ntawm cov ntaub so ntswg loj hlob kev ntxhov siab. Qhov kawg tshwm sim yog cov ntaub so ntswg kev nyuaj siab tensile kev nyuaj siab, lub plawv feem compressive kev nyuaj siab, thiab thermal stress nyob rau hauv raws nraim qhov opposite. Cov kev ntxhov siab nyob rau hauv lub workpiece loj thiab txias npaum li cas ntawm martensite transformation cheeb tsam, cov duab, tshuaj muaj pes tsawg leeg ntawm cov khoom.