151results about How to "Play the role of diffusion strengthening" patented technology

The invention relates to binary lead-free solder paste for welding and surface mounting of electronic components. Nanopowder is added based on micron lead-free solder paste; and the solder paste comprises the following compositions in percentage by mass: 90 to 99 percent of micron lead-free solder paste and 0.1 to 10 percent of the nanopowder, wherein the nanopowder is nanopowder of ordinary lead-free solder paste or nanopowder of metal or nanopowder of SiC, SiN, BN, and AL2O3. The binary lead-free solder paste has the entire basic performances of the ordinary lead-free solder paste, and reduces the cost and the melting point. Compared with the prior tin lead solder paste, the binary lead-free solder paste does not contain toxic element lead, and is particularly suitable for electronic packaging technology in the microelectronic industry.

The invention relates to steel for a Ca microalloying free-cutting high-strength expansion-breaking connecting rod. The steel is prepared from, by mass percent, 0.25%-0.60% of C, 0.10%-1.20% of Si, 0.40%-1.50% of Mn, 0.05%-0.50% of Cr, 0.02%-0.15% of S, 0.02%-0.15% of P, 0.03%-0.55% of V, 0.0005%-0.0080% of Ca, 0.002%-0.035% of N, 0.002%-0.080% of Al, not larger than 0.02% of Ti and the balance Fe and inevitable impurity elements. The steel is subjected to smelting, continuous casting, heating, hot rolling and cooling, and the structure characteristic is uniform ferrite and pearlite. According to the steel, key elements in the steel are optimized, Ca microalloying is especially adopted, and the steel for the expansion-breaking connecting rod with high strength, good cutting machinability, good expansion-breaking performance and excellent comprehensive performance is obtained, and the design requirements for engine light weight, economical efficiency and driving comfort are met.

The invention provides a preparation method of (TiV)C steel bond hard alloy. Titanium and vanadium whose ratio is 1:1 are prepared, and a mixture and graphite powder are prepared into in-situ synthesized (TiV)C mixed powder, wherein the atomic mole ratio between C and Ti+V is 0.7-1.1; ferrovanadium powder, ferrochromium powder, ferromolybdenum powder, ferroboron powder, ferrous powder, ferrosilicon powder, ferromanganese powder, nickel powder, copper powder, colloidal graphite and a rare earth raw material are prepared according to a required mass ratio of bonded-phase metal chemical components, ball-milling is carried out by a steel ball, absolute ethanol as a medium and PVA (polyvinyl alcohol) are added, after the ball-milling is finished, slurry is dried and pressed for forming, and the steel bond alloy is obtained. In situ reaction synthesis technology and liquid phase sintering technology are combined, and the (TiV)C steel bond hard alloy is prepared. (TiV)C is synthesized in situ in a substrate through reaction in the sintering process, the fineness of particles is improved, no sharp angle is formed on the surface, and a substrate interface is relatively good in adhesion and clean. The comprehensive mechanical property of the alloy can be improved, the price is low, and the process is simple and convenient.

The invention relates to a preparation method of ultrahigh-manganese steel based TiC steel bond hard alloy. The preparation method is characterized by comprising the following steps: preparing titanium powder and graphite powder into in-situ synthesized TiC powder with the required proportion according to the C / Ti atomic ratio of 0.8-1.0; preparing ferromolybdenum powder, ferrovanadium powder, ferrochromium powder, ferromanganese powder, ferrosilicon powder, iron powder, nickel powder, colloidal graphite and rare earth raw materials according to the required mass ratio of bonded-phase metal chemical components, performing ball-milling by a steel ball, adding absolute ethanol as a medium and PVA (polyvinyl alcohol), after the ball-milling process is finished, drying slurry, pressing for forming, and sintering to obtain the steel bond alloy. According to the preparation method, the ultrahigh-manganese steel based TiC steel bond hard alloy is prepared by combining an in-situ reaction synthesis technology with a liquid-phase sintering technology; as TiC is synthesized in situ in a substrate through reaction in the sintering process, the fineness of particles is improved, no sharp angle is formed on the surface, and a substrate interface is relatively good in adhesion and clean; the comprehensive mechanical property of the alloy can be improved, the price is low, and the process is simple and convenient.

The invention relates to a preparation method of a TiC high-wear-resistant steel-bonded hard alloy. The preparation method is characterized by comprising the following steps: using titanium powder and graphite powder to prepare in-situ synthesized TiC powder according to the atomic ratio 0.7-1.1 of C to Ti; mixing ferrochromium powder, ferromolybdenum powder, ferrovanadium powder, ferrotungsten powder, ferroniobium powder, nickel powder, ferroboron powder, iron powder, colloidal graphite and a rare earth material according to the chemical component mass ratio of the bonding phase metals; filling the mixed powder in a steel ball mill; adding absolute ethyl alcohol as a medium and PVA (Polyvinyl Acetate) to the ball mill; after ball milling, drying the obtained slurry, pressing, molding and sintering the dried substance to obtain the steel-bonded hard alloy. The preparation method disclosed by the invention combines the in-situ reaction synthesis technology with the liquid-phase sintering technology to prepare the TiC high-wear-resistant steel bonded hard alloy. As TiC is prepared by in-situ synthesis inside the substrate through the reaction during the sintering process, the reinforced particle size is fine, the surface is free of sharp corners, the substrate interface bonding effect is good, and the interface is clean. The preparation method for the steel-bonded alloy can improve the comprehensive mechanical property of the alloy, and is low in price and simple and convenient in the technology.

The invention discloses a high-strength high-ductility CNTs-SiCp enhanced aluminum-based composite material which comprises the following components: less than or equal to 5vol.% of a carbon nano tube, less than or equal to 5 vol.% of silicon carbide particles and the balance aluminum powder. A preparation method for the high-strength high-ductility CNTs-SiCp enhanced aluminum-based composite material comprises the following steps of: adding raw material components and grinding balls into a ball-milling tank in proportion, adding a process control agent into the ball-milling tank, ball-milling and dispersing under the protection of inert gases, thereby obtaining uniformly dispersed mixed powder; filling a graphite mould with the mixed powder, pre-pressing the mixed powder, and sintering pre-pressed block bodies; and pre-heating a sintered and formed composite material in a tubular furnace under the protection of inert gases, and carrying out thermal extrusion, thereby obtaining the CNTs-SiCp enhanced aluminum-based composite material. The CNTs-SiCp enhanced aluminum-based composite material has very good mechanical property, and also keeps high ductility and high electrical conductivity.

The invention relates to a high-entropy alloy coating resistant to high-temperature abrasion and a preparation process and application thereof. The preparation process comprises the following steps: (1) the surface of a titanium alloy sample is polished and washed; (2) metal powder, a ceramic hard phase and rare earth oxide are evenly mixed, and cladding material powder is formed to be flatly laidon the washed surface of a titanium alloy; and (3) the titanium alloy coating is prepared through laser cladding, wherein the metal powder includes Ti, Ni, Al, Si and V, a ceramic phase material is B4C or TiC or TiN, and the rare earth oxide is Y2O3. According to the high-entropy alloy coating, the hardness of a titanium alloy part can be remarkably improved, abrasion resistance of the titanium alloy part is improved, and the using range of the titanium alloy part is enlarged.

The invention discloses a high ferrochrome roller used for a large-sized wide and thick plate rolling mill. The high ferrochrome roller comprises a roller core, a roller neck and a roller body workinglayer. The roller body working layer comprises, by mass, 2.40%-3.30% of C, 0.60%-1.00% of Si, 0.90%-1.20% of Mn, 15.00%-18.00% of Cr, 1.10%-1.70% of Ni, 0.80%-1.40% of Mo, 0.10%-0.60% of V, 0-0.10% of S, 0-0.05% of P, and the balance Fe and inevitable impurities. By adjusting the heat treatment technology, the mechanical property of the roller is improved, the abrasion resistance and millimeter rolling quantity of the roller are increased, and the service life of the roller is prolonged.

The invention discloses laser cladding coating powder and a preparation method thereof. The laser cladding coating powder is prepared from the components by mole: 90%-99% of TiAl powder and 1%-10% ofB powder; and the preparation method comprises the steps of metal matrix selection and pretreatment, powder matching and ball milling, powder presetting, and laser cladding. TiAl and B make an in-situreaction through the effect of a CO2 laser beam, and a TiAl based alloy coating with TiB and TiB2 as reinforcing phases is prepared on the surface of a metal matrix. According to the laser cladding coating powder and the preparation method thereof, the hardness of the laser cladding coating is high, good wear resistance and corrosion resistance are achieved, and the laser cladding coating is bonded to the matrix in a metallurgical mode and the bonding condition is good.

The invention relates to the production field of aluminum alloys, in particular to a method for restraining generation of an A7N01 aluminum alloy surface coarse grain ring. During alloy smelting, a trace rare earth element, namely scandium, is led in, the weight percentage of the scandium is 0.05%-0.15%, and a scandium contained A7N01 aluminum alloy casting ingot is prepared. The casting ingot is subject to homogenization treatment, extrusion forming, online air cooling and natural aging treatment, the defect of the coarse grain ring on the surface of an extrusion product is restrained, and the alloy microstructure is obviously refined. An A7N01 aluminum alloy comprises, by mass percentage, 4.0%-5.0% of zinc, 1.0%-2.0% of magnesium, not larger than 0.20% of copper, 0.20%-0.7% of manganese, not larger than 0.30% of chromium, not larger than 0.25% of zirconium, not larger than 0.20% of titanium, not larger than 0.10% of vanadium and the balance aluminum and inevitable impurities. According to the method, the trace rare earth element, namely scandium, is led in, a wee dispersed nanoscale Al3(Sc,Zr) phase is generated in an A7N01 aluminum alloy extrusion bar base, and the dispersion strengthening effect is achieved.

The invention relates to a preparation method of a high-strength high-conductivity high-softening-temperature copper-clad dispersion copper conductive rod, and specifically relates to the technical field of vacuum switch arc extinguish chamber conductive rod materials. The method comprises the following steps: 1) preparation of dispersion copper alloy powders; 2) preparation of a core dispersion copper rod through a cold isostatic pressing method, pressing pressure being 150-300 MPa, and pressure dwell time being 3-10 min; 3) vacuum sintering of the core dispersion copper rod, maximum sintering temperature being 800-1080 DEG C, temperature holding time being 30-240 min, and vacuum degree being larger than 5 pa; 4) preparation of an outer copper sleeve; 5) embedding the core dispersion copper rod into the outer copper sleeve and carrying out vacuum electron beam sealing; 6) extrusion, extrusion temperature being 600-1050 DEG C; and 7) cold drawing. The conductive rod has the advantagesof high strength, high conductivity, high softening temperature and good soldering performance and the like, and fully meets use requirements of the arc extinguishing chamber conductive rod.

The invention discloses a monoblock cast all-purpose horizontal high-chromium cast iron collar. The monoblock cast all-purpose horizontal high-chromium cast iron collar is composed of two mixing components, one component comprises, by mass, 1.70-2.10% of C, 0.40-1.00% of Si, 0.70-1.20% of Mn, 0.20-1.30% of Ni, 10.00-20.00% of Cr, 0.50-1.50% of Mo, less than or equal to 0.03% of S, less than or equal to 0.03% of P and the balance Fe and inevitable impurities; and the other mixing component comprises, by mass, 0.70-1.20% of C, 1.30-1.90% of Si, 0.50-0.80% of Mn, less than or equal to 0.50% of Ni, less than or equal to 0.50% of Cr, less than or equal to 0.15% of Mo, less than or equal to 0.03% of S, less than or equal to 0.03% of P and the balance Fe and inevitable impurities. Meanwhile, the preparation method of the high-chromium cast iron collar is further disclosed. The produced high-chromium cast iron collar is high in hardness and good in abrasion resistance, and meanwhile the high-chromium cast iron collar has long service life.

The invention belongs to the technical field of aluminum alloy production process, and relates to a six-series aluminum alloy template and a production process thereof. The six-series aluminum alloy template is prepared from the following elementary compositions in percentage by weight: 0.50-0.55 % of Si, 0.10-0.15 % of Fe, 0.05-0.10 % of Cu, 0.05-0.10 % of Mn, 0.55-0.60 % of Mg, less than or equal to 0.05 % of Cr, less than or equal to 0.05 % of Zn, less than or equal to 0.05 % of Ti, less than or equal to 0.25 % of La, less than or equal to 0.05 % of other single impurity content, less thanor equal to 0.15 % of total impurity, and the balance of Al. Through the improvement of alloy composition and production process, the final six-series aluminum alloy template has tensile strength of 280 Mpa, yield strength of 255 Mpa and elongation after fracture of 12.5 %, the mechanical properties are significantly improved, and the production needs of customers can be met.

The invention discloses a high-air-tightness low-free-oxygen-content nano disperse copper alloy and a short-process preparation technology, and wherein the alloy components comprise Al2O3, Ca and La.The preparation technology is made by the following steps that preparing Cu-Al2O3 alloy powder by adopting an internal oxidation method, and then mixing the Cu-Al2O3 alloy powder with Cu-Ca-La alloy powder, wrap covering the mixed powder under the protection of argon, carrying out hot extrusion at 900-920 DEG C and then rotary forging, after rotary forging, the wrap covering is vacuumized to be less than or equal to 10<-3>Pa, the wrap covering is sealed and is placed in a nitrogen atmosphere with the temperature of 450-550 DEG Cand the pressure intensity of 40-60 Mpa for 3-5 hours. According to the preparation technology disclosed by the invention, the secondary solid reduction of Ca and La is utilized, so that residual free oxygen is effectively removed and the dispersion strengthening effect is achieved, and finally the high density is obtained through vacuum medium-temperature creep deformation. The disperse copper prepared by the invention has the advantages that low free oxygen content (<= 15ppm), high dimensional stability and good air tightness after hydrogen annealing, good in gas tightness, the gas leakage rate is less than or equal to 1.0*10<-10> Pa.m<3> / s, the preparation technology is suitable for industrial production and can be used as a variety of sealing device materials such as an electric vacuum shell sealing device and a novel energy automobile high-voltagedirect-current relay.