Martensitic stainless steel Martensitic stainless steel Martensitic stainless steel is a specific type of stainless steel alloy. Stainless steels may be classified by their crystalline structure into three main types: "austenitic", "ferritic" and "martensitic". Martensitic stainless steels can be high- or low-carbon steels built around the Type 410 composition of iron, 12% chromium, and up to 1.2% carbon. They are hardenable by heat treatment (specifically by quenching, or by quenching and tempering). The alloy composition, and the high cooling rate of quenching enable the formation of martensite. Tempered martensite gives steel good hardness and high toughness; used largely for medical tools (scalpels, razors
SAE 904L stainless steel systems. In 1985 Rolex became the first wristwatch manufacturer to utilize 904L grade steel in its watches. Rolex chose to use this variety of steel because it takes a higher polish than other grades of steel and provides greater corrosion resistance, though it does not machine as well and requires specialized equipment to be properly modified into the required shapes. SAE 904L stainless steel 904L is an austenitic stainless steel. In comparison to 316L, its molybdenum addition gives it superior resistance to localized attack (pitting and crevice corrosion) by chlorides and greater resistance reducing acids and in particular its copper