Dislocation Density Based Plasticity Model Coupled with Precipitate Model

A dislocation density based plasticity model is applied to two variants of steels. One is an austenitic (fcc) stainless steel with ordered precipitates and the other is a Ti-Nb microalloyed (bcc) steel. Precipitate distributions are measured and this information is combined with appropriate precipitate hardening models. The flow stress model is also calibrated for an nickel-based superalloy where it is combined with a model for precipitate growth.

Transport Modeling and Compensation Mechanism for Semi-Insulating LT-Gaas and InP: Cu

ABSTRACTThe compensation mechanism and transport properties of annealed GaAs grown by molecular beam epitaxy at low substrate temperature (LT-GaAs) and Cu diffused InP are analyzed by using a deep donor band model and a precipitate model. It was found that the compensation in highly resistive LT GaAs can not be explained by the precipitate model alone, and therefore a high donor density had to be considered. In Cu diffused InP, the precipitate model gives a consistent explanation for the observed carrier compensation and mobility data. For both semi-insulating LT-GaAs and fully-compensated, lightly-doped InP:Cu, the neutral impurity scattering was found to be a major carrier scattering mechanism.