Stellite 1

Stellite 1 achieves extensive M₇C₃ and M₆C type hard carbides (with hardness up to 1500-1800 HV) through its 'high carbon, high chromium, high tungsten' composition design, which are uniformly distributed within a cobalt-based solid solution matrix. This 'hard particle + tough matrix' composite structure enables it to effectively resist cutting and adhesive wear by abrasive particles. Typical hardness ranges for cast or weld-deposited conditions are between HRC 50-60 (approximately HV 550-720). Under dry friction conditions, its wear rate against quenched steel is only 1/20 that of 304 stainless steel and 1/5 that of weld overlay wear-resistant steels (e.g., D517). Even at temperatures above 400°C, its wear resistance degradation remains below 15%, far outperforming iron-based wear-resistant alloys (degradation >50%).

Stellite 1 yog qhov txawv los ntawm nws qhov siab tshaj - kub hardness, tswj qhov hnyav hnyav txawm tias siab tshaj 760℃(1400℃F)- khaws kwv yees li 37 HRC ntawm 600℃thiab txog 28 HRC ntawm 870℃(1600℃F). Cov cuab yeej zoo no yog los ntawm kev hloov pauv ntawm allotropic ntawm cobalt los ntawm hexagonal ze-packed (ε-Co) mus rau lub ntsej muag-centered cubic (-Co) saum chav tsev kub, nrog rau cov khoom- kev daws teeb meem los ntawm tungsten. Hauv cov huab cua oxidizing, cov ntsiab lus siab chromium txhawb kev tsim cov Cr₂O₃ oxide zaj duab xis rau saum npoo; Tom qab raug huab cua ntawm 800℃rau 1000 teev, oxidation hnyav nce tsawg dua 1 mg / cm², muab oxidation zoo dua li cov hlau feem ntau -raws li cua sov{21}}cov hlau resistant. Cov hlau ua pov thawj zoo heev microstructural stability thaum lub sij hawm ntev - cov kev pab cuam saum toj no 600 degree, tsis muaj theem tseem ceeb transformation los yog softening.

Nrog kwv yees li 30% chromium cov ntsiab lus thiab cov khoom siv hauv lub cev ntawm cobalt matrix, Stellite 1 qhia tau zoo corrosion kuj nyob rau hauv ntau yam corrosive media. Nyob rau hauv chav tsev kub, nws resists sulfuric acid concentrations txog li 50%, hydrochloric acid mus txog 30%, thiab tag nrho cov concentrations ntawm sodium hydroxide tov, feem ntau nrog corrosion nqi qis dua 0.1 mm / a. Nyob rau hauv oxidizing xov xwm xws li nitric acid, nws corrosion kuj tseem surpasses ib co npib tsib xee-raws li alloys. Hauv cov dej hiav txwv thiab cov tshuaj chloride, Stellite 1 feem ntau ua rau pitting ntau dua li cov khoom poob qis, nrog rau cov khoom siv hluav taws xob raug kwv yees li ntawm -0.4 V (SCE). Txawm li cas los xij, kev ua tau zoo yog txwv hauv kev txo cov kua qaub (xws li, hydrochloric acid) thiab fluorine{16}} muaj cov xov xwm. Tsis tas li ntawd, oxide zaj duab xis tuaj yeem raug puas tsuaj yooj yim nyob rau hauv kev sib txhuam kev sib txhuam, uas yuav tsum tau siv cov roj nplua nyeem kom muaj kev tiv thaiv corrosion.

Stellite 1 nthuav tawm cov khoom siv kho qhov muag uas yog 'siab hardness thiab qis ductility': tensile zog ntawm chav tsev kub yog kwv yees li 550-1000 MPa, tab sis elongation tom qab tawg tsuas yog 1-3%, thiab cuam tshuam lub zog (Charpy V-notch) yog<10 J, classifying it as a typical wear-resistant brittle material. Therefore, it is unsuitable for applications subject to severe impact loads but performs exceptionally well in sliding wear and fretting wear conditions. The alloy is typically formed via precision casting or powder metallurgy. Weld overlay (PTA, TIG, oxy-acetylene) is the most common application method for Stellite 1. Due to its high susceptibility to hot cracking, preheating to 300-600°C and control of interpass temperature are required during welding, followed by slow cooling post-weld to reduce crack tendency. Because of its extremely high hardness, grinding or electrical discharge machining (EDM) are recommended for finishing operations.