Archive for the ‘Heat treatment of steels’ Category
Friday, March 17th, 2006
Carburizing is a case-hardening process in which carbon is dissolved in the surface layers of a low-carbon steel part at a temperature sufficient to render the steel austenitic, followed by quenching and tempering to form a martensitic microstructure. The resulting gradient in carbon content below the surface ...
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Friday, March 17th, 2006
Nitriding is a surface-hardening heat treatment that introduces nitrogen into the surface of steel at a temperature range (500 to 550°C, or 930 to 1020°F), while it is in the ferrite condition. Thus, nitriding is similar to carburizing in that surface composition is altered, but different in ...
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Friday, March 17th, 2006
Carburizing is the addition of carbon to the surface of low-carbon steels at temperatures generally between 850 and 950°C (1560 and 1740°F), at which austenite, with its high solubility for carbon, is the stable crystal structure. Hardening is accomplished when the high-carbon surface layer is quenched to ...
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Tuesday, March 14th, 2006
Surface hardening a process which includes a wide variety of techniques is used to improve the wear resistance of parts without affecting the softer, tough interior of the part. This combination of hard surface and resistance and breakage upon impact is useful in parts such as a ...
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Tuesday, March 14th, 2006
Thermomechanical treatment involves the simultaneous application of heat and a deformation process to an alloy, in order to change its shape and refine the microstructure. Thus, hot-rolling of metals, a well-established industrial process, is a thermomechanical treatment which plays an important part in the processing of ...
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Tuesday, March 14th, 2006
Alloy steels are defined as those steels that:
contain manganese, silicon, or copper in quantities greater than the maximum limits (1.65% Mn, 0.60% Si, and 0.60% Cu) of carbon steel; or
that have specified ranges or minimums for one or more other alloying additions.
The low-alloy steels are those steels containing ...
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Tuesday, March 14th, 2006
For considering heat treatment of this group, several typical tool steels are selected as examples, designated only by the type letter and numeral as used in the USA and the UK for standardized tool steels, e.g. H13, O1. These designations are so well known by steel consumers ...
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Saturday, March 11th, 2006
Two steels have been chosen from this group as examples for the discussion, grade O1 (RT 1733) and Swedish SIS 2092 (SR 1855).
When carbon steel is used for punching dies or cold hobbing tools the dimensions of the tool are bound by a ruling section that is determined ...
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Saturday, March 11th, 2006
Reckoned on a tonnage basis, tool steel represents only a few percent of the total quantity of steel produced but its importance to the industry as a whole is immense. Regrettably this fact is seldom sufficiently appreciated. Perhaps in greatest measure this applies to the heat treatment ...
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Saturday, March 11th, 2006
Wire ropes for haulage purposes are usually made from carbon steel wires ranging from 0,35 to 0,5% carbon, and before drawing the material is subject to a heat-treatment known as patenting.
Patenting consists of passing the wire through tubes in a furnace at about 970oC. This high temperature ...
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