To support quantitative design of ultra-high-strength (UHS) secondary-hardening steels, the precipitation of cementite prior to the precipitation of the M2C phase is investigated using a model alloy. The microstructure of cementite is investigated by transmission electron microscopy (TEM) techniques. Consistent with earlier studies on tempering of Fe-C martensite, lattice imaging of cementite s...

An artificial neural network has been used to model the irradiation hardening of lowactivation ferritic/martensitic steels. The data used to create the model span a range of displacement damage of 0 90 dpa, within a temperature range of 273 973 K and contain 1800 points. The trained model has been able to capture the non-linear dependence of yield strength on the chemical composition and irradi...

Industrial applications require parts of components with specific surface properties such are good corrosion resistance, wear resistance and hardness. Alloys with those properties are usually very expensive and there is a great interest in reducing the cost of components for fulfilling these requirements. In this sense, laser surface processing has been used as a cost-effective technique to imp...

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A series of medium-carbon low alloy steels was quenched to martensite and tempered at 150 C. This low-temperature-tempered (LTT) martensite was subjected to uniaxial tensile and impact testing. Yield and ultimate tensile strength and uniform elongation increased, and post uniform and total elongation and fracture toughness decreased, with increasing carbon concentration. The carbon dependence o...

Exploration of new energy resources located in areas of complex ground and ambient climate imposes strict requirements on pipeline material and design. One of the major research issues in such areas is differential ground movement, which, possibly, is associated with large longitudinal straining in addition to plastic circumferential elongation. Hence, common design principles need thorough re-...