4D Quench – single-piece flow vacuum heat treatment as modern alternative to a press hardening
Material distortion is an undesired characteristic observed when a produced component requires a thermo-chemical heat treatment process followed by a rapid quench to obtain desired mechanical and metallurgical properties including a uniform case depth and hardness profile. Due to the distortion taking place during this process, the manufacturer is faced with the costly choice of leaving excess material on a machined component before the heat treatment process, only to be removed after the heat treatment process by post heat treatment manufacturing methods. When steps are taken to reduce material distortion (prior to hard machining operations), manufacturers can significantly reduce the component cost and subsequently speed up the overall manufacturing process.
This paper will discuss the unique method of distortion control for heat treated and quenched components by use of a 4-Dimensional High-Pressure Gas Quench (4D HPGQ) technique. This system has the ability to quench a single component without fixturing versus either a free quench or complex press quench approach. The 4D HPGQ process results in each component being individually quenched in an identical manner while having minimal distortion in relation to the green component. 4D HPGQ systems are easily integrated into machining centers improving lead time and costs associated with traditional heat treatment processes.
Keywords: Single-piece flow, case hardening, low pressure carburizing, high pressure gas quench, in-line manufacturing, lean manufacturing, mass production, distortion, quenching, press quench