Selection of materials for use in railway applications is an extremely precise process due to intense use and very high loading.
Structural integrity is therefore critical with specific requirements ranging from high fracture toughness, weldability, good fatigue characteristics and all for relatively low material production costs.
Monthly Archives: February 2013
Strain Ageing of Steel: Part One
Strain ageing of steel was first observed during the 19th century when the maximum load carrying capacity of a test piece was increased after it had been retested after a previous series of testing in the plastic range.
General acceptance has been recognized that strain ageing is due to the diffusion of carbon and/or nitrogen atoms in solution to dislocations that have been generated by plastic deformation however the resulting characteristics are the result of a complex series of metallurgical reactions.
True Stress – True Strain Curve: Part Four
This article describes strain-hardening exponent and strength coefficient, materials constants which are used in calculations for stress-strain behaviour in work hardening, and their application in some of the most commonly used formulas, such as Ludwig equation.