Archive for the ‘Steels’ Category
Monday, February 18th, 2008
This article describes how NDT, FTE, FTP are used in engineering design through the fracture analysis diagram (FAD).
Temperature dependence of yield strength, tensile strength, and fracture strength is explained, as well as influence of various initial flaw sizes and the dynamic tear test (DT), as a highly versatile test both ...
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Monday, February 18th, 2008
Three basic factors contribute to a brittle-cleavage type of fracture. They are
1. a triaxial state of stress,
2. a low temperature, and
3. a high strain rate or rapid rate of loading.
The Brittle – Fracture Problem
During World War II a great deal of attention was directed to the brittle failure of welded ...
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Monday, February 18th, 2008
Significant variables, which determine ductility of steels, are to be found in the steel-making process, where the nature and distribution of inclusions is partly determined, and in subsequent solidification and working processes. Likewise, the carbide distribution will depend on composition and on steel-making practice, and particularly on the final heat ...
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Monday, February 18th, 2008
There are several forms of embrittlement in steel like intergranular embrittlement, temper embrittlement, embrittlement caused by overheating and burning.
While cleavage fracture in steels is a common form of embrittlement, in many cases the embrittlement is intergranular (IG), i.e. it takes place along the grain boundaries, usually the former austenitic boundaries. ...
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Monday, February 18th, 2008
Most groups of alloys can exhibit failure by cracking in circumstances where the apparent applied stress is well below that at which failure would normally be expected. Steels are no exception to this, and probably exhibit a wider variety of failure mechanisms than any other category of material. While ultimate ...
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Wednesday, February 13th, 2008
The oxygen steelmaking process is a generic name given to those processes in which gaseous oxygen is used as the primary agent for autothermic generation of heat as a result of the oxidation of dissolved impurities like carbon, silicon, manganese and phosphorus and to a limited extent the oxidation of ...
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Wednesday, February 13th, 2008
Deoxidation is the removal of excess oxygen from molten metal. The procedure involves adding materials with a high affinity for oxygen, the oxides of which are either gaseous or readily form slags. The deoxidation of steel is usually performed by adding Mn, Si and Al, or rarely by adding Cr, ...
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Wednesday, February 13th, 2008
In the history of research and development of stainless steels, most important has been the decarburization of high chromium molten steel. Efficient decarburization and the prevention of chromium oxidation losses have been central to the development of steelmaking technology for stainless steels.
Because the strong affinity of chromium for carbon, all ...
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Wednesday, February 13th, 2008
Boron is useful as an alloying element in many materials, but in this paper it will be illustrated as an alloying element in the steel because of its effect on hardenability enhancement. Boron is added to unalloyed and low alloyed steels to enhance the hardness level through enhancement hardenability. Boron ...
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Wednesday, February 13th, 2008
This article describes effect of phosphorus on the texture and drawability (R value), spot weldability, magnetic properties and coating properties of carbon steels.
Texture (R-Value)
Anisotropy of plastic-flow properties has a strong influence on the deep drawability of sheet steels. For good drawability the through-thickness strength in order to avoid thinning during ...
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