This paper reports on the precipitation behaviour and microstructural evolution in ~20% cold rolled NbMoV and V single microalloyed low carbon steels during intercritical annealing. The microstructure and precipitation behaviour were studied by optical and scanning/transmission electron microscopy and microanalysis, X-ray diffraction technique and Vickers hardness testing. After intercritical a...

Formation and evolution of a carbide superlattice (SL) during C deposition on Mo have been studied using molecular beam epitaxy techniques. The ordering of the SL is energetically driven, such that the interplay between strain and surface energies determines the length scale of the SL. Surface precipitation of C occurs within a narrow range of SL spacing that appears to control the size and spa...

The precipitation, coarsening and reversion of carbides can determine the quality of steels. This paper is a review of efforts towards better, practical theory for all of these solid–state reactions.

The influence of precipitates and dislocations on the acoustic nonlinearity was investigated in isothermally aged ferritic CrMo steel and low cycle fatigued copper. The variation in the normalized acoustic nonlinearity parameter (β/β0) was interpreted as resulting from microstructural changes supported by the electron microscopy. The β/β0 of CrMo steel increased abruptly in the initial stage of...

Warm laser shock peening (WLSP) is a thermomechanical treatment technique combining the advantages of laser shock peening and dynamic strain aging (DSA). Through DSA, WLSP of steel increases the dislocation density and stabilizes the dislocation structure by pinning of mobile dislocations by carbon atoms. In addition, WLSP generates nanoscale carbide precipitates through strain-induced precipit...

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...

The atomic-scale nucleation mechanism of vapor-grown carbon nanofibers (CNFs) is investigated using classical molecular dynamics simulations with a developed parameterization. Carbon precipitation and graphene plane formation are simulated, taking into account the carbon concentration (CC) in Ni carbide. The simulated results show that the carbon atoms formed sp(2) networks or sp chains in the ...