Forgings

Adding vanadium as an alloying element to 5CrNiMo die steel can refine its grain structure, improving its wear resistance and thermal fatigue performance. Forging can further refine the grain structure of the new vanadium-containing hot work die steel 5CrNiMoV sample, further enhancing the wear resistance and thermal fatigue performance of 5CrNiMoV die steel.

The austenitization of Cr12MoV steel at 1100-1150 ℃ allows almost all carbides to dissolve in the austenite, followed by rapid spheroidization at 720 ℃ → 750 ℃ → 720 ℃ immediately after rapid cooling, which can completely eliminate network carbides and large pointed carbides, and eliminate the inheritance of coarse structures. After final heat treatment, the grain size can reach 10-12 levels, and the carbide particles are refined and round, which greatly increases the impact toughness of the steel and prolongs the service life of the mold.

Adopting appropriate forging processes can effectively adjust the ratio of α phase and γ phase in dual-phase steel forgings, thereby enhancing the mechanical properties and corrosion resistance of the forgings: (1) Heating the cold ingot of duplex stainless steel to 1160~1180℃ for cogging and elongation forging, and crushing the as-cast crystalline structure of duplex stainless steel can refine the grain size of the billet. Water cooling after forging effectively prevents the precipitation of harmful phases such as σ. (2) After the second heating forging process, the billet undergoes upsetting and drawing, leading to further grain refinement. Various casting defects diffuse at high temperatures, dispersing uniformly or being eliminated.

This article employs a two-step melting process to produce alloy ingots with varying carbon contents. Subsequently, through processes such as forging, solution treatment, testing, and analysis, target alloy forgings are fabricated. The results indicate that when the carbon content in the alloy falls within a specific range, the alloy exhibits both excellent corrosion resistance and superior high-temperature performance. The comprehensive performance of the product meets the requirements for use in China's aerospace, energy, nuclear reactor, and other fields.

The heat treatment process of forged steel cold rolling rolls mainly includes post forging heat treatment, overall quenching and tempering treatment of the roll, deep quenching and tempering treatment of the roll body. Some cold rolling work rolls also require deep cryogenic treatment to increase the depth of the quenching layer and reduce the residual austenite content. Among them, post forging heat treatment, as a heat treatment process for roll forging, includes forms such as normalizing and spheroidizing annealing, mainly used to improve the matrix structure, eliminate stress, and improve machining and cutting performance. The overall quenching and tempering treatment of the rolling mill includes quenching and high-temperature tempering. After quenching and tempering treatment, the rolling mill substrate has good strength, toughness, plasticity, and mechanical processing properties.

Die forging and casting are two key manufacturing processes used to create metal parts, each with distinct advantages depending on the application. Die forging involves shaping metal using high pressure in a die, resulting in parts with superior strength, toughness, and precision.