3 results about "Pinning points" patented technology

The invention discloses a sparse and dense stacked nonlinear electromagnetic ultrasonic detection transducer and a pipeline creep detection device, and relates to the technical field of pipeline creep damage detection. The sparse coil (namely the first coil) with the distance between the wires equal to the half-wavelength of the fundamental frequency ultrasonic waves and the dense coil (namely the second coil) with the distance between the wires equal to the quarter-wavelength of the fundamental frequency ultrasonic waves are arranged in a stacked mode to form the sparse and dense stacked coil. Fundamental frequency ultrasonic waves with enough strength can be effectively excited to enter a material of a detected pipeline, and nonlinear ultrasonic response signals (namely second harmonic signals) generated by lattice nonlinear change caused by early creep micro-damage (such as micro-voids, grain boundary slippage and dislocation pinning point weakening) in the material are captured and enhanced in a high-sensitivity manner; and timely and reliable technical guarantee is provided for safe operation of the pipeline.

The invention provides a permalloy structural part and a selective laser melting manufacturing method and application thereof, and relates to the technical field of soft magnetic materials. According to the selective laser melting manufacturing method of the permalloy structural component, the selective laser melting manufacturing process with low power, moderate scanning speed and small track spacing is adopted, lattice distortion and point defects are reduced from the source, the initial grain orientation is controlled, grain growth is more uniform, iron and nickel atoms are more orderly arranged in fcc lattices, and the performance of the permalloy structural component is improved. The density and the structure uniformity are improved; and then a combined process of high vacuum and inert protective atmosphere-high temperature diffusion-slow recrystallization along with furnace cooling-rapid cooling and rapid magnetic domain stabilization is utilized, lattice distortion in the permalloy structural part is avoided, residual stress is released, lattice defects are repaired, crystal form transformation is promoted, the grain size is uniform, formation of pinning points of a magnetic domain wall is inhibited, and the performance of the permalloy structural part is improved. And finally, the soft magnetic performance of the permalloy structural member is comprehensively improved.

The application relates to the technical field of semiconductor device manufacturing, in particular to a preparation method of an oxide layer and a semiconductor device prepared by the method. The method comprises the following steps: pre-treating a substrate under a pre-treatment atmosphere containing nitrogen to form dislocation pinning points on the surface of the substrate; performing thermal oxidation treatment on the substrate under an oxidation atmosphere containing nitrous oxide to form an oxide layer with a preset thickness on the surface of the substrate; during the thermal oxidation treatment, nitrogen atoms formed by the decomposition of the nitrous oxide are combined with vacancies in the substrate lattice to further form nitrogen-vacancy clusters at the dislocation pinning points, the dislocation lines are directly pinned, the movement of the dislocation lines on the slip plane is inhibited, and oxygen formed by the decomposition of the nitrous oxide is oxidized. The method can fundamentally inhibit the movement of the dislocation lines on the slip plane, and effectively solves the problems of long dislocation slip and accumulation caused by stress and other factors in the thermal oxidation process.