1. Cov khoom siv yog tooj dag?
Cov yam ntxwv tseem ceeb ntawm Brass:
Chemical Composition Foundation: Copper feem ntau suav rau 55% -95% ntawm cov hlau, thaum zinc ua rau 5% -45%. Qhov piv ntawm Cu rau Zn ncaj qha txiav txim siab tooj dag lub zog:
High- tooj dag tooj liab (piv txwv li, 70% Cu + 30% Zn): Zoo heev ductility, corrosion kuj, thiab machinability, haum rau kev tsim thiab vuam.
High-zinc tooj dag (piv txwv li, 60% Cu + 40% Zn): Ntau zog thiab hardness tab sis txo ductility, zoo tagnrho rau castings los yog cov khoom uas yuav tsum tau rigidity.
Mechanical Properties: Feem ntau pom muaj zog tensile zoo (200-600 MPa, nyob ntawm seb muaj pes tsawg leeg thiab kev kho cua sov), nruab nrab hardness (50-150 HB), thiab zoo formability (tuaj yeem dov, extruded, forged, los yog kos rau hauv ntau yam duab).
Corrosion Resistance: Resistant corrosion los ntawm huab cua, dej, thiab feem ntau tsis yog - oxidizing acids (xws li, hydrochloric acid nyob rau hauv tsawg concentrations) tab sis tej zaum yuav tarnish thaum lub sij hawm (cov ntaub ntawv tiv thaiv oxide tiv thaiv ntxiv degradation). Ntxiv ntawm tin (naval tooj dag) txhim khu kev tiv thaiv rau seawater corrosion.
Lwm Qhov Zoo: Cov khoom siv hluav taws xob zoo thiab thermal conductivity (tsis zoo rau cov tooj liab ntshiab tab sis zoo dua rau cov hlau feem ntau), cov khoom siv tshuaj tiv thaiv kab mob, thiab cov tsos zoo nkauj zoo nkauj (siv hauv cov ntawv thov zoo nkauj).
Classification ntawm Brass:
Binary Brass (Cu-Zn nkaus xwb): Yooj yim alloy ntawm tooj liab thiab zinc, piv txwv li, tooj liab liab (siab Cu ntsiab lus, ~ 85% Cu) thiab daj tooj dag (sib npaug Cu-Zn, ~ 65% Cu).
Ternary / Quaternary tooj dag: Alloyed nrog cov ntsiab lus ntxiv los txhim kho cov khoom tshwj xeeb:
Leaded tooj dag (Cu-Zn-Pb): Enhanced machinability (lead ua raws li cov roj nplua nyeem thaum txiav), siv rau fasteners thiab li qub.
Naval tooj dag (Cu-Zn-Sn): Superior corrosion resistance to seawater, siv nyob rau hauv marine hardware thiab shipbuilding.
Aluminium tooj dag (Cu-Zn-Al): siab zog thiab corrosion kuj, haum rau siab - kub lossis siab - kev siv siab.
