43results about How to "Reduced activation energy for diffusion" patented technology

The invention discloses a copper-based pre-alloyed powder additive used for a diamond tool and a preparation method thereof. The copper-based pre-alloyed powder additive comprises the following raw materials including, by weight, 85-95 parts of alloyed powder and 2-5 parts of fiberglass; the alloyed powder is chemically composed of, by mass, 6-9 parts of phosphorus, 2-5 parts of tin, 20-35 parts of copper, and further comprises, by mass, 1-4 parts of nickel, 0-1 part of silicon, 0-0.1 part of hafnium; the fiberglass is modified fiberglass powder; and after the alloyed powder made in a gas-water atomization method and the modified fiberglass powder are subjected to ball milling, the final copper-based pre-alloyed powder additive is prepared. The pre-alloyed powder additive prepared throughthe preparation method is lower in melting point, and a high edge sharpening height of diamond and strong holding force of a matrix to the diamond are guaranteed.

The invention relates to an aluminosilicate glass and a preparation method and application thereof. The preparation method comprises the following steps: taking corresponding glass raw materials according to the set content of each component of the aluminosilicate glass and mixing them uniformly, wherein the glass The raw material contains Al(PO 3 ) 3 powder; carry out high temperature melting, clarification, leakage forming and annealing of the uniformly mixed raw materials to obtain aluminosilicate glass; preheat the tempered molten salt to a molten state, wherein the tempered molten salt includes potassium nitrate, sodium nitrate, phosphoric acid Potassium and potassium carbonate; the prepared glass is immersed in molten tempered molten salt, and chemically tempered to obtain a strengthened aluminosilicate glass. In the preparation method of the aluminosilicate glass of the present invention, by adding potassium phosphate and potassium carbonate to the molten salt, a better strengthening effect can be achieved and the service life of the molten salt can be ensured.

The invention provides a method for preparing a rare earth metal-boron binary co-infiltration layer on the surface of molybdenum or molybdenum alloys, wherein the molten salt system is first pretreated before electrochemical binary co-infiltration, and the pretreatment process is as follows: : Put the molten salt system into the sealed seepage tank, pressurize and keep warm in the seep tank, the pressurized pressure is 0.3-0.7MPa, the keep-warm temperature is 100°C-300°C, and the pressurization time is 0.5-1h. The molybdenum or molybdenum alloy with binary co-infiltration layer prepared by the method of the present invention has good high temperature oxidation resistance and can resist high temperature oxidation corrosion; the La-B binary co-infiltration layer prepared by the method is compatible with molybdenum or molybdenum alloy substrate Good capacity, not easy to crack, not easy to fall off. The service temperature of molybdenum or molybdenum alloy after surface binary co-infiltration treatment can reach 1500 ℃.

The invention relates to a method and device for sintering synchronous connection of metal matrix composite materials assisted by pulsed electric field and ultrasonic field, and discloses a method for connecting a magnesium (or copper) matrix composite material containing a high volume fraction reinforcing phase to stainless steel while sintering. The devices involved in this method include: a closed heating furnace, a pulse current loading system, an ultrasonic load applying system, a pressure and lifting system, and auxiliary devices such as sealed insulating tubes. The significant advantage of adopting the present invention is that the sintering of the metal matrix composite material and the connection of different materials are carried out simultaneously; the pulse current flows through the experimental material, causing interface resistance heat and plasma discharge heat, and the sintering and connection interface temperature rises and cools quickly, reducing external radiation heat, reduce the residual stress of the joint; use the coupling effect of pulsed electric field-ultrasonic field-pressure field to break the oxide film on the surface of the reinforcement phase, realize sintering under atmospheric conditions, reduce the activation energy of atomic diffusion, promote the interface metallurgical reaction, and control the particle shape and size , refine the interface grains, improve the quality and stability of the joint, and is conducive to the preparation of metal matrix composites / alloy joints with high comprehensive performance.

The invention discloses a preparation method for a Ti-Al system gradient protective screen material, and the preparation method improves sample connecting performance through a method of improving anatom contact area at a diffusion welding physical contact stage. The preparation method specifically comprises the following steps of: (1) selecting and designing a gradient protective screen body system; (2) performing orientated grinding treatment on the surface of a to-be-connected Ti / Al system sample; (3) performing oriented assembly on the Ti / Al system to-be-welded sample; and (4) performinglow-temperature connection on the Ti / Al system sample. The preparation method can realize low-temperature high-strength connection between the titanium alloy and the aluminum alloy; the prepared Ti-Algradient material is good in welding joint combination, is simple and convenient to operate and is small in control difficulty in comparison with a conventional welding joint, is low in preparation temperature, is low in cost, is free of an intermetallic compound, is small in joint residual stress and is extremely good in performance; and the Ti-Al system gradient protective screen material has shear strength of 128 MPa, and is used as a gradient protective screen which is novel and reasonable in structural design in comparison with a conventional protective screen, is small in density and isgood in protective effect.