Hnav cov yam ntxwv ntawmcov khoom sib txhuam
Txhawm rau ua kom lub braking thiab kis tau zoo, peb xav tau cov khoom sib txhuam kom muaj kev sib txhuam coefficient siab thiab ruaj khov nyob rau hauv qhov sib txawv ntawm qhov kub thiab txias, nyob rau hauv qhov sib txawv txav ceev thiab loads, thiab kuj muaj kev tiv thaiv zoo rau kev puas tsuaj thiab kev pab cuam lub neej. Cov khoom siv sib txhuam muaj qhov sib txhuam thiab hnav cov yam ntxwv hauv qab no.
1. Thermal recession
Lub matrix (piv txwv li, lub binder) ntawm cov khoom sib txhuam yog cov thermosetting phenolic resin lossis roj hmab. Thaum lub phaj kev sib txhuam yog nyob rau hauv tus txheej txheem ntawm braking thiab kis tau tus mob, qhov kev sib txhuam nto ntawm nws thiab cov hlau dual cov ntaub ntawv yuav ua rau ib tug kub heev kub, ncav cuag 200 ~ 400.degree, los yog siab dua. Qhov no tau mus txog lub thermal decomposition kub cheeb tsam ntawm resins thiab rubbers.
Lub sijhawm no, cov macromolecules tsim cov kua lossis gaseous tsawg-molecular cov khoom vim thermal degradation, tsim cov kua nyias nyias los yog gaseous nruab nrab txheej ntawm kev sib txhuam, los yog cov txheej nruab nrab nruab nrab tsuas yog npog ib feem ntawm qhov chaw, ua rau cov kev sib txhuam zoo tib yam. los yog qhuav kev sib txhuam Cov kev ua hauj lwm yuav yog cov ntaub ntawv ntawm kev sib txhuam kev sib txhuam, uas yog reflected raws li ib tug txo los yog ib tug ntse txo nyob rau hauv lub coefficient ntawm kev sib txhuam ntawm macroscopic theem, uas yog hu ua thermal recession. Lub thermal decay tshwm sim tuaj yeem pom meej meej thaum cov khoom sib txhuam ntawm cov qauv kev sib txhuam yog ntsuas los ntawm kev sib txhuam tester.
2. Thermal hnav thiab thermal tawg
Thaum cov phaj sib txhuam nyob rau hauv qhov kub thiab txias ua hauj lwm ntev ntev, thermal decomposition ntawm resin los yog roj hmab macromolecules yog intensified, molecular lub ntsiab saw thiab cross-linked saw ntawm lub polymer yog tawg, lub network qauv raug rhuav tshem, thiab tsis tshua muaj molecular. cov khoom raug tsim thiab khiav tawm. Qhov tshwm sim ntawm thermal decomposition yog carbonization thiab tsis zoo ntawm resins thiab rubbers. Carbonization ua rau cov resin poob nws cov cohesive nyhuv, thiab qhov poob ntawm qhov zoo yuav txo tau tus nqi ntawm binders, uas ua rau gradual tsim ntawm cov kab nrib pleb nyob rau hauv cov ntaub ntawv ntawm kev sib txhuam, ua rau cov hnav, thiab tej zaum txawm cov khoom ntog tawm ntawm lub nto ntawm cov khoom. kev sib txhuam hauv ob sab phlu thiab poob nws txoj haujlwm ua haujlwm.
Yog li ntawd, thaum lub sij hawm ntev-kub kub ntau lawm (los yog kis tau tus mob) ua hauj lwm ntawm cov khoom sib txhuam, lub thermal decomposition thiab thermal poob ntawm cov resin thiab roj hmab nyob rau hauv cov qauv yog intensified, lub hnav ntawm cov kev sib txhuam phaj yog intensified, thiab lub kev pab cuam lub neej luv luv.
Los ntawm cov saum toj no, nws tuaj yeem pom tias qhov kub tsis kam ntawm resin thiab roj hmab yog qhov tseem ceeb heev los txo cov thermal recession, thermal hnav thiab thermal tawg ntawm kev sib txhuam hauv ob sab phlu.
