37results about How to "Reduce crack growth rate" patented technology

The invention belongs to the technical field of further processing of grain, and in particular relates to a process for optimizing the production of germinated brown rice. The process is characterized in that the engineering method is used to simulate according to the natural germinating process of rice in a soil environment condition, the high germination rate and high gamma-aminobutyric acid content in germinated brown rice are the targets, and on that basis, the optimization process parameter combination meeting the demands on water absorption, temperature, ventilation and other conditions for germination of brown rice are obtained. Compared with the traditional brown rice germination process, the process, provided by the invention, has the advantages that the link of soaking is avoided, so that the natural germination rules of brown rice are met, no sewage is produced, the loss on dissolution of nutritional substances of the brown rice in soaking is avoided, and the energy consumption for drying of the germinated brown rice due to excessive water sucking in the soaking link can also be decreased. With the adoption of the process for optimizing, the germination rate of brown rice can be increased by 5 to 7%, and the gamma-aminobutyric acid content in germinated brown rice can be increased by about 2.4 times.

The invention relates to hot die steel which comprises the following components in percentage by weight: 0.32-0.42 percent of carbon, 0.2-0.5 percent of silicon, 0.2-0.5 percent of manganese, 2.2-2.7 percent of chromium, 1.0-3.4 percent of molybdenum, 0.8-2.2 percent of tungsten, 0.4-0.6 percent of vanadium, 0.2-1.5 percent of cobalt and the balance of Fe. A tempering process of the hot die steelcomprises the following steps of: firstly, tempering at 440-460 DEG C for 1-2 hours and then cooling to room temperature; then tempering at 520-560 DEG C for 1-2 hours and then cooling to room temperature; and finally, tempering at 520-560 DEG C for 1-2 hours and then cooling to room temperature. The hot die steel has the characteristics of high heat resistance and high toughness. The tempering process greatly reduces the fracture speed of materials and further improves the toughness of die materials.

The invention discloses a low-noise steel rail for bridge cranes, which consists of the following components according to mass percentage, C: 3.4%-3.6%, Si: 2.4%-2.6%, Mn: 0.3%-0.5%, P: ≤0.02%, S: ≤0.02%, Cr: ≤0.3%, Cu: 0.3%~0.5%, Mg: 0.03~0.045%, the balance is Fe, the sum of the mass percentages of the above components is 100%; The tensile strength is ≥880MPa, the elongation is ≥8%, and the surface hardness of the top surface is ≥55HRC. The invention also discloses a method for preparing a low-noise steel rail for bridge cranes. Suppresses the vibration and noise transmitted by the crane truss.

The invention relates to a treatment method for a brass texture antifatigue aluminum alloy panel, which is characterized in that multiple times of warm rolling is performed on an aluminum alloy hot rolling material until reaching the designed thickness of the aluminum alloy panel, and after annealing treatment and solution treatment, short-term artificial aging is performed. According to the invention, a treatment process of multiple times of warm rolling and annealing is adopted; by virtue of warm rolling, grains of the alloy can be effectively refined, the return process of alloy can be promoted, deformation energy storage can be reduced, and recrystallization can be inhibited; and by virtue of primary annealing treatment, annealing temperature and heat insulation time can be controlled, grains cannot grow up, and a deformation texture can be retained, thus obtaining a relatively strong deformation texture. The treatment method is simple in process method and convenient to operate, can effectively improve the composition and the volume fraction of the texture in an aluminum alloy matrix, can effectively prolong the fatigue life of the aluminum alloy on the premise of ensuring that aluminum alloy strength and ductility meet alloy performance requirements, is suitable for industrial application, and provides a feasible technical solution for preparation of aluminum alloy material for aviation and spaceflight.

The invention discloses an alloyed high manganese steel frog and its manufacturing process. The chemical composition (wt%) of the frog is: C: 0.95-1.35, Mn: 11.0-14.0, Cr: 0.2-1.0, Mo: 0.2~1.2, V: 0.05~0.35, Si: 0.3~0.8, Ni: 0.002~1.5, Re: 0.001~0.05, Mg: 0.001~0.005, P:≦0.045, S:≦0.03, and the rest is Fe. The alloyed high manganese steel frog prepared by the invention has a grain size 1-2 grades smaller than that of common high manganese steel frogs, which can improve the toughness of the high manganese steel frogs, reduce the crack growth rate and increase the service life.

The invention relates to a granular delta-phase uniformly distributed GH4169 alloy preparation method and belongs to the technical field of preparation of high-temperature alloy materials. On the basis of combination of cold deformation and heat treatment processes, the method includes GH4169 alloy cold deformation and heat treatment. Firstly, plate blanks are subjected to cold rolling deformation more than 30% after solid solution and quickly cooled under vacuum argon shielding after heat preservation at 985+ / 5 DEG C for 1h; secondly, the plate blanks are subjected to standard double aging treatment; finally, granular delta phases uniformly distributed in grains and at grain boundaries of GH4169 alloy are acquired. Therefore, GH4169 alloy strength is improved, and crack growth rate of the GH4169 alloy is decreased to acquire better fatigue performance.

The invention relates to a welding structure of a metal defect digging-patching welding groove of a steel casting and a reinforcing method of the welding structure. By adoption of the welding structure of the metal defect digging-patching welding groove of the steel casting and the reinforcing method of the welding structure, the technical problems that during digging-patching welding of an existing large cast steel component, deformation of a welding structure is difficult to control, a repair welding area is likely to crack, and the structural stability and fatigue resistance of the weldingstructure cannot be guaranteed easily can be solved. The reinforcing method comprises the steps of first, welding a shell structure; second, arranging a plurality of rows and columns of multi-stage internal steel webs at intervals in the longitudinal and horizontal directions of a weld joint and the depth direction of the groove; third, filling welding deposited metal in a separated space of the welding groove; and fourth, conducting facing welding on the surface of the welding groove. According to the reinforcing method, a shell and rigid framework three-dimensional welding structural systemconstructed through welding can resist and disperse the shrinkage stress of weld joint metal, the welding deformation is effectively controlled, the stability of the welding structure is improved, propagation of fatigue cracks is changed, and accordingly, the propagation rate of the cracks is decreased.