1. Saib machined nto
Grey hlau: grey, tsaus heev gloss, ntxhib nto. Ductile hlau: grey, lub gloss yog ci dua li ntawm grey hlau, thiab qhov saum npoo roughness zoo ib yam li cov hlau grey.
2. Kev xeem ntawv
Grey hlau: Cov ntaub ntawv tiv thaiv qis, muaj lub suab "swoosh" thaum ua ntaub ntawv, tsis tshua muaj nplaum, lub swarf yog grey-dub, nrog ob peb xim-dawb ci me ntsis. Sib tsoo nrog koj cov ntiv tes, nws yooj yim rau blacken koj cov ntiv tes. Ductile hlau: Thaum ua ntaub ntawv, qhov kev tiv thaiv yog me ntsis loj dua li cov hlau grey, thiab tseem muaj lub suab "swoosh" ntau pom tseeb, tsis tshua ua rau cov ntaub ntawv, cov plua plav yog grey-dub, nrog cov xim zoo nkauj, thiab cov particle. qhov loj sib txawv, tab sis cov khoom loj yog cov feem ntau. Tus Tswv, kev sib tsoo cov plua plav nrog koj cov ntiv tes tuaj yeem ua rau cov ntiv tes dub, tab sis cov degree ntawm blackening yog sib dua li cov hlau grey.
3. Mloog zaj nkauj
Grey Hlau: Lub suab qis, lub sijhawm luv heev. Hlau Hlau: Lub suab yog nkig, nrog reverberation thiab luv luv.