Search results
Results from the WOW.Com Content Network
Coke being pushed into a quenching car, Hanna furnaces of the Great Lakes Steel Corporation, Detroit, Michigan, November 1942. In materials science, quenching is the rapid cooling of a workpiece in water, gas, oil, polymer, air, or other fluids to obtain certain material properties.
Tempering is most often performed on steel that has been heated above its upper critical (A 3) temperature and then quickly cooled, in a process called quenching, using methods such as immersing the hot steel in water, oil, or forced-air. The quenched steel, being placed in or very near its hardest possible state, is then tempered to ...
Martempering is also known as stepped quenching or interrupted quenching. In this process, steel is heated above the upper critical point (above the transformation range) and then quenched in a hot-oil, molten-salt, or molten-lead bath kept at a temperature of 150-300 °C. The workpiece is held at this temperature above martensite start (Ms ...
Cooling speeds, from fastest to slowest, go from brine, polymer (i.e. mixtures of water + glycol polymers), freshwater, oil, and forced air. However, quenching certain steel too fast can result in cracking, which is why high-tensile steels such as AISI 4140 should be quenched in oil, tool steels such as ISO 1.2767 or H13 hot work tool steel ...
White steel 1 is difficult to forge and to quench due to its higher carbon and can become harder and more brittle than White 2. A water quench with these traditional steels and processes will result in a blade that is harder, stiffer, sharper with longer lasting sharpness but that is more difficult to sharpen and relatively less tough.
The quenching converts the billet's surface layer to martensite, and causes it to shrink. The shrinkage pressurizes the core, helping to form the correct crystal structures. The core remains hot, and austenitic. A microprocessor controls the water flow to the quench box, to manage the temperature difference through the cross-section of the bars.
Martensitic transformation, more commonly known as quenching and tempering, is a hardening mechanism specific for steel. The steel must be heated to a temperature where the iron phase changes from ferrite into austenite, i.e. changes crystal structure from BCC (body-centered cubic) to FCC (face-centered cubic). In austenitic form, steel can ...
The term hardened steel is often used for a medium or high carbon steel that has been given heat treatment and then quenching followed by tempering. The quenching results in the formation of metastable martensite, the fraction of which is reduced to the desired amount during tempering. This is the most common state for finished articles such as ...