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 distenge pa siperyè segondè -tanperati cho dite li, kenbe konsiderab dite menm pi wo pase 760 degre (1400 degre F) - kenbe apeprè 37 HRC nan 600 degre ak apeprè 28 HRC nan 870 degre (1600 degre F). Pwopriyete eksepsyonèl sa a soti nan transfòmasyon alotropik kobalt soti nan egzagonal fèmen {-ko) pou fè fas a-santre kib (-Co) anlè tanperati chanm, ansanm ak solid-solisyon ranfòsman tengstèn bay. Nan atmosfè oksidan, kontni an segondè Kwòm ankouraje fòmasyon nan yon fim oksid dans Cr₂O₃ sou sifas la; apre yo fin ekspoze nan lè a 800 degre pou 1000 èdtan, pran pwa oksidasyon an mwens pase 1 mg/cm², ki ofri pi bon rezistans oksidasyon pase pi fè -ki baze sou chalè- asye ki reziste. Alyaj la montre ekselan estabilite mikwostriktirèl pandan sèvis alontèm ki pi wo pase 600 degre, san okenn transfòmasyon faz enpòtan oswa ralantisman.

Avèk apeprè 30% kontni chromium ak pwopriyete nannan nan matris la cobalt, Stellite 1 demontre bon rezistans korozyon nan divès medya korozivite. Nan tanperati chanm, li reziste konsantrasyon asid silfirik jiska 50%, asid idroklorik jiska 30%, ak tout konsantrasyon solisyon idroksid sodyòm, tipikman ak pousantaj korozyon anba a 0.1 mm / a. Nan medya oksidan tankou asid nitrique, rezistans korozyon li yo menm depase kèk alyaj ki baze sou nikèl -. Nan dlo lanmè ak solisyon klori, Stellite 1 prensipalman sibi pitting olye ke pèt mas inifòm, ak yon potansyèl elektwòd tipik apeprè -0.4 V (SCE). Sepandan, pèfòmans limite nan asid fòtman diminye (egzanp, asid idroklorik) ak fliyò -ki gen medya yo. Anplis de sa, fim nan oksid ka fasil domaje anba kondisyon friksyon ki gen gwo estrès, ki mande pou itilize grès machin yo kenbe rezistans korozyon.

Stellite 1 montre pwopriyete mekanik ki karakterize pa 'segondè dite ak ba duktilite': fòs rupture nan tanperati chanm se apeprè 550-1000 MPa, men elongasyon apre ka zo kase se sèlman 1-3%, ak enèji enpak (Charpy V-dan) se.<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.