35results about How to "Improve room temperature toughness" patented technology

The present invention relates to a high-strength Mg-Gd-Y-Zn-Mn alloy. The alloy comprises the following alloying elements distributed in the alloy, by weight, 8.2-10.2% of Gd, 5.0-6.0% of Y, 0.5-4.0% of Zn, 0.5-0.8% of Mn, and the balance of Mg and inevitable impurities. The alloy is prepared by adopting the following process: material preparing, vacuum melting and ingot casting, uniformization annealing, extrusion and heat treatment. According to the present invention, Mg, Zn, Gd and Y form a large amount of long period phases in the Mg-Gd-Y-Zn-Mn alloy so as to provide a significant dispersion strengthening effect, and the time effect treatment is adopted to introduce the strengthening effect of the metastable phase; the process is a preparation method for the high-strength deformation Mg alloy, wherein the method integrates solid solution strengthening, precipitation strengthening and deformation strengthening; the method has characteristics of simple process, strong portability, easy operation and low cost; with the method, tensile strength and yield strength of the allay at the room temperature are significantly improved, and difficulty of allay application limitation due to low mechanical property is solved so as to expand the application range of the Mg alloy.

The invention relates to high-toughness cold-hot-fatigue-resistant cast steel for a high-speed train brake disc and a preparation method thereof, belongs to the field of metal materials and preparation thereof, and solves the problem of matching of room-temperature toughness, high-temperature mechanical properties and cold and hot fatigue failure resistance of the cast steel for the high-speed train brake disc in the prior art. The high-toughness cold-hot-fatigue-resistant cast steel for the high-speed train brake disc comprises the following chemical components, in percentage by mass, of 0.20%-0.40% of C, 0.30%-0.70% of Si, 0.50%-2.00% of Mn, 0.50%-2.00% of Cr, 0.50%-2.00% of Ni, 0.40%-1.80% of Mo, 0.01%-0.30% of V, smaller than or equal to 0.015% of P, smaller than or equal to 0.010% ofS, smaller than or equal to 0.010% of O, smaller than or equal to 0.015% of N, and the balance Fe and inevitable impurities, wherein the total content of the Mn, the Cr and the Ni is 2.00%-6.00%, andthe total content of the Mo and the V is 0.41%-2.00%. Through reasonable composition, organization structure and preparation process regulation and control, excellent room-temperature toughness, high-temperature mechanical property and cold and hot fatigue failure resistance of the cast steel are matched, the requirements for comprehensive mechanical property and long service life of the cast steel brake disc of a high-speed train are met, and the cast steel is suitable for being used as a material for the cast steel brake disc of the high-speed train.

The invention belongs to the field of biomedical materials and particularly relates to a titanium oxide-titanium carbide whisker toughened magnesium alloy biomedical material. The titanium oxide-titanium carbide whisker toughened magnesium alloy biomedical material is composed of magnesium alloy substrate material powder and titanium oxide-titanium carbide whisker powder; the magnesium alloy substrate material powder and the titanium oxide-titanium carbide whisker powder are uniformly mixed through a mechanical mixing method; the mixed powder is subjected to cold pressing, vacuum heating degassing and vacuum sintering; and a heat pressing ingot is subjected to equal channel deformation, so that the titanium oxide-titanium carbide whisker toughened magnesium alloy biomedical material is obtained. The toughness, the abrasion resistance and the strength of in-situ generated titanium oxide-titanium carbide whisker toughened magnesium alloy are remarkably improved, and the in-situ generated titanium oxide-titanium carbide whisker toughened magnesium alloy is especially suitable for the biomedical material and also can be applied to parts such as high-end sports car magnesium alloy hubs requiring for high strength and high abrasion resistance.

The invention relates to a method for preparing and controlling a second phase homogenization in a high-aluminum-content cast-rolled magnesium alloy plate. The method comprises the following steps ofheating stepped solid solution treatment, high-temperature multi-pass rolling deformation, cooling multi-pass rolling deformation and recrystallization annealing treatment. By means of the method, a mesh-strip-shaped segregation second phase of a millimeter-scale size in an initial tissue is eliminated, a fine near-spherical second phase with uniform dispersion distribution is obtained, and the fine crystal structure is obtained at the same time. According to the method, a method combining heat treatment and common rolling is adopted, and no barrier is implemented in industrial production. Theproblem that the high-aluminum-content cast-rolled magnesium alloy is difficult to deform and serious in rolling cracking is solved, so that a magnesium alloy sheet material which is good in macroscopic morphology, uniform in microstructure and super-close in comprehensive performance is obtained.

The invention discloses a high-temperature-resistant multi-component silicide coating on the surface of niobium alloy and a preparation method of the high-temperature-resistant multi-component silicide coating. The high-temperature-resistant multi-component silicide coating has the phase composition of [(Nb(1-x-y)TixCry)(1-z),Rz]Si2, wherein R is one or more of the metal elements of Mo, W, Zr, Hfand Ta; x, y and z respectively represent mole numbers of the corresponding elements; 0.05<=x<=0.2; 0.05<=y<=0.3; and 0.05<=z<=0.4. The preparation method comprises the following steps: first, metal elementary powder and silicon elementary powder are weighed and thrown into a mixer to be fully mixed for 12-24 h; the mixed multi-component metal powder covers a niobium alloy workpiece, then, the covered niobium alloy workpiece is placed in a graphite crucible, and the graphite crucible is placed in a discharge plasma sintering furnace for sintering; and a sample of the sintered coating is subjected to homogenization heat treatment in a vacuum or protective atmosphere. The invention provides the discharge plasma sintering and homogenization heat treatment compounded preparation process. The process is simple. The coating structure is homogeneous. Ingredients are controllable. The coating has favorable high-temperature oxidation resistance at 1,200-1,600 DEG C.

The invention relates to a polyethylene composite material for injection molding and a preparation method thereof, and belongs to the technical field of high polymer materials. The polyethylene composite material for injection molding is mainly prepared from auxiliaries and the following raw materials in parts by weight: 20-30 parts of coupling agent modified calcium carbonate, 50-70 parts of high-density polyethylene, 20-40 parts of linear low-density polyethylene and 10-20 parts of a toughening agent, wherein the melt index of the HDPE is 6-10 g/10 min, and the melt index of the LLDPE is 1-3g/10min. The material realizes the balance of rigidity and toughness and is suitable for injection processing because of fluidity, the toughness and environmental cracking resistance are improved by the LLDPE, the normal-temperature toughness and low-temperature toughness are improved by the toughening agent, and the coupling agent modified calcium carbonate and the polymer have good compatibility, so that the polyethylene composite material for injection molding has enough rigidity and heat resistance, and the material can maintain better performance in high-temperature, normal-temperature and low-temperature environments.

The invention belongs to the field of metal materials; and in order to improve the defect of lower toughness of a traditional commercial cast magnesium alloy, metal Zn and Y are added in an AM50 alloyto develop a high-strength cat magnesium alloy and a preparation method thereof. The magnesium alloy comprises the following components in percentage by mass: 4.9-5.0% of Al, 3.1-3.4% of Zn, 0.7-0.75% of Y, 0.25-0.3% of Mn, impurity element Si not more than 0.03%, the total content of other impurities Fe, Ni and Cu not more than 0.01%, and the balance of Mg. The alloy has the advantages of low cost, simple melt treatment, excellent casting performance and higher toughness, is easy to popularize and apply, in particular, is suitable for large-scale commercial production, and achieves higher market potential. The room-temperature mechanical performance indexes of the alloy are higher than that of the commercial AM50 alloy.