Cov khoom siv hluav taws xob ntawm cov hlau yog cov cim tseem ceeb los xyuas kom meej qhov ua tau zoo tshaj plaws (cov khoom siv kho tshuab) ntawm cov hlau, uas nyob ntawm cov tshuaj muaj pes tsawg leeg thiab kev kho cua sov ntawm cov hlau. Nyob rau hauv cov qauv steel yeeb nkab, raws li cov kev xav tau sib txawv, cov khoom tensile (lub zog tensile, yield zog los yog yield point, elongation), hardness, toughness indicators, as well as user requirements for high and low temperature performance.
① Tensile zog (σ B)
Qhov siab tshaj plaws quab yuam (Fb) uas cov qauv dais ntawm qhov tawg thaum lub sij hawm ncab, muab faib los ntawm kev ntxhov siab tau los ntawm kev faib cov thawj ntu ntu ntu (Yog li) ntawm cov qauv ( σ), hu ua tensile zog ( σ b) Chav tsev yog N/mm2 (MPa). Nws sawv cev rau lub peev xwm siab tshaj plaws ntawm cov ntaub ntawv hlau los tiv thaiv kev puas tsuaj nyob rau hauv lub zog tensile.
② Yield point (σ S)
Qhov kev ntxhov siab ntawm cov khoom siv hlau nrog cov khoom tshwm sim tuaj yeem txuas ntxiv mus ntxiv yam tsis muaj kev nce ntxiv (tso tseg) lub zog thaum lub sijhawm tensile txheej txheem hu ua qhov taw tes tawm. Yog tias lub zog txo qis, cov ntsiab lus sab saud thiab qis dua yuav tsum tau paub qhov txawv. Chav tsev ntawm qhov taw tes tawm yog N / mm2 (MPa).
Upper yield point( σ Su): Qhov siab tshaj plaws ntawm cov qauv ua ntej yielding thiab thawj qhov txo qis hauv quab yuam; Lower yield point( σ SL): Qhov kev ntxhov siab yam tsawg kawg nkaus nyob rau theem yield thaum pib qhov tshwm sim instantaneous tsis suav nrog.