Tool steels chromium

High speed steels are highly alloyed tool steels which exhibit enhanced hardness and wear resistance at high temperatures. These steels have a high carbon content and varying amounts of chromium, molybdenum, tungsten and vanadium. 

For tool steels, a letter followed by one or two numbers. For example, D2 belongs to a family of high carbon, high chromium tool steels known as cold work tool steels. All members of this family have the prefix D. 

A.P.G. Gervasio, G.C. Luca, A.A. Menegario, B.F. Reis, H. Bergamin-Filho, On-line electrolytic dissolution of alloys in flow injection analysis. Determination of iron, tungsten, molybdenum, vanadium and chromium in tool steels by inductively coupled plasma atomic emission spectrometry, Anal. Chim. Acta 405 (2000) 213. 

Mold design. PTFE resins are molded in molds similar to those utilized for thermosetting resins or metal powders. A complete mold consists of a cylindrical or rectangular die and upper and lower end plates and a mandrel for annular parts. These parts are normally made of tool steel to allow machining, and plated with chromium or nickel to protect them from corrosion. Occasionally, the end plates are made of brass or plastics such as nylon. A small diametrical clearance is designed in the end plates to allow easy assembly and air escape. 

Injection molds are machined from a variety of tool steels and then hardened or in some cases plated with chromium, nickel, or proprietary materials. Large molds use prehardened tool steels because they cannot be hardened after machining. 124 Stainless steel is employed for some smaller molds, particularly those used for optical and medical parts and for corrosion resistance. Since they provide better heat transfer and, thus, shorter molding cycles, materials such as beryllium copper are used as inserts in critical areas. Injection molds are usually cooled or heated with water, although oil or electric heater cartridges are employed for high-mold temperatures. Mold-temperature controllers pump water into the manifolds and then into cooling fine machine into the molds. 

Mold tool steels P These are special-purpose tool steels containing chromium and nickel as major alloying elements. They exhibit low hardness and low resistance to work hardening when annealed. 

Nickel (Ni). Nickel is usually used in combination with other alloying elements, such as chromium, to improve the fracture toughness and, to some extent, the wear resistance of tool steels. 

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