33results about How to "Improve resistance to high temperature oxidation" patented technology

The invention mainly relates to the coating technique, in particular to a gradient MCrAlY coating used for protecting high-temperature alloy and a preparation method thereof. The invention prepares an MCrAlY composite gradient coating by adopting the method combining the arc ion plating (AIP) and the diffusion aluminizing. The thickness of an aluminum-rich layer on the surface of the MCrAlY composite coating can be controlled by setting the aluminizing temperature and the period of heat preservation and the Al elements are distributed in a gradient way along the depth direction; in addition, the chemical vapor deposition method used for the aluminizing has the advantages of good uniformity on the aluminum-rich layer and being not affected by the size and shape of a sample. Since the method of direct diffusion is adopted without introducing a weak interface, the MCrAlY high-temperature protective coating can increase the content of Al memory phase to the utmost extent under the condition that the mechanical property of the coating is guaranteed, so as to improve the high-temperature oxidization resistance and the heat corrosion resistance of the coating, and can effectively prolong the service life of the coating. The MCrAlY composite gradient coating and the preparation method of the invention can be applied to the protection of Ni-based and Co-based high-temperature alloys.

A stainless heat-proof self-protecting flux-cored wire for a magnesium smelting reduction tank belongs to the technical field of materials processing engineering. A normal stainless steel band 304L or common carbon steel serves as a coating layer, and alloys in a powder core are rutile, sodium carbonate, feldspar, compound fluorides, chromium, nickel, manganese, molybdenum, chromium nitride, aluminium-magnesium alloy, misch metal and iron power. Compared with a conventional stainless steel welding rod, the stainless heat-proof self-protecting flux-cored wire has the advantages that higher welding current can be used; higher welding speed can be realized; the production efficiency is improved; and the labor intensity is lowered; c. Compared with a conventional stainless steel submerged-arc welding solid wire, the stainless heat-proof self-protecting flux-cored wire has the advantages that all-position welding can be realized; the heat input is small; the slag detachability is good; and the manufacturing technique is simpler. A welded joint formed by using the stainless heat-proof self-protecting flux-cored wire provided by the invention has favorable heat resistance, oxidation resistance, vulcanization and corrosion resistance and high-temperature creep resistance compared with welded joints formed by welding the stainless steel welding rod and the stainless steel solid wire.

The invention provides a nano composite ceramic coating, a pressure casting die and a preparation method of the pressure casting die and belongs to the technical field of preparation of coatings and pressure casting dies. The problems that existing pressure casting dies are poor in property and short in service life are solved. The nano composite ceramic coating comprises a Cr metal bonding layer, a CrN transition layer arranged on the Cr bonding layer, a supporting layer arranged on the CrN transition layer and a function layer arranged on the supporting layer. The supporting layer is a nano periodical TiSiN-CrAlN structural coating of a gradient structure, and the function layer is a nano composite TiCrAlSiN structural coating. The invention further provides the pressure casting die prepared with the composite ceramic coating and further provides the preparation method of the pressure casting die. The nano composite ceramic coating has the bonding force exceeding 70 N, the internal stress being smaller than 0.15 Gpa and the hardness being higher than 35 GPa, and the service life of the pressure casting die is three times or above longer than that of common pressure casting dies.

The invention provides a super-thick super-hard coating and a preparation method thereof. The super-thick super-hard coating comprises a Ti bottom layer deposited on the surface of a basal body, a TiN transitional layer prepared on the Ti bottom layer, and a TiAlSiCN coating prepared on the TiN transitional layer; and the thickness of the super-thick super-hard coating is larger than or equal to 20 microns. During preparation, a columnar electric arc Ti target serves as a Ti source; a planar magnetron sputtering Si target, a planar magnetron sputtering Al target and a planar magnetron sputtering target serve as sources of Si, Al and C correspondingly; Ar serves as an ionization gas; and N2 serves as a reaction gas. According to the invention, the binding force of the basal body to a TiAlSiCN coating as well as the thickness of the TiAlSiCN coating prepared on the basal body is remarkably improved; and as elements such as Si, C and Al are added into the TiN coating, the TiAlSiCN coating with five elements is obtained, and the hardness, the abrasion resistance, the anti-friction quality, the high-temperature oxidization resistance and the corrosion resistance of the coating are further improved.

The invention provides a turbine blade assembly thermal barrier coating. The turbine blade assembly thermal barrier coating comprises a bonding layer, an aluminide layer, an aluminum oxide layer and a ceramic layer which are sequentially arranged in an upward mode from a turbine blade assembly base material or comprises an aluminide layer, a bonding layer, an aluminum oxide layer and a ceramic layer which are sequentially arranged. The bonding layer is a MCrAlY layer, and M represents one or two or three sorts of nickel, cobalt and iron. According to the thermal barrier coating system provided by the invention, the high-temperature oxidation resistance, thermal corrosion resistance and endurance property of the thermal barrier coating are improved on the premise that the thermal barrier effect of the thermal barrier coating is guaranteed, and thus the service life of a turbine blade assembly is prolonged. By means of the thermal barrier coating system prepared through the method, the weight of the blade assembly can be lowered obviously, and therefore the creep degree of the assembly by tension of the turbine blade assembly in the high-speed rotating process is decreased and the service life of the turbine blade assembly is prolonged.

The invention discloses an integral repair method for the longitudinal intensive damage of a blade crown of an aero-engine turbine rotor blade. The integral repair method for the longitudinal intensive damage of the blade crown of the aero-engine turbine rotor blade comprises the following steps of firstly mechanically grinding the blade, integrally removing a damaged blade crown, adopting laser for repairing cracks under a casting cover plate, and fixing a blade tip cover plate onto the blade crown of the blade; then adopting an integral type laser solid forming technology for integrally forming the blade crown, manually processing a formed blade crown surface, and recovering a runner type surface; and finally, carrying out nondestructive testing on the repaired turbine blade, and puttinginto use after the blade meets a criterion. According to the integral repair method for the longitudinal intensive damage of the blade crown of the aero-engine turbine rotor blade provided by the invention, the integral repairing method is adopted, so that not only is degradation material removed thoroughly, but also the one-by-one repair process is avoided, and the workload is reduced; and meanwhile, through using a special repair material, a combination property of the crown material is improved.

The invention provides a TiB<w>-Ti composite layer and a laser in-situ preparation method thereof. Specifically, the composite layer is prepared from the raw materials: Ti powder and TiB2 powder, a melting layer with a gradient change of TiB<w>/Ti content is prepared on the surface of a substrate, the melting layer is remelted, and a cladding layer is prepared on the surface of a remelting layer by means of a synergistic effect of induction heating and laser quenching. In the cladding layer, the interface structure of alpha-Ti and TiB<w> is in the form of coherent combination or semi-coherentcombination, and the strength and toughness, the high-temperature oxidation resistance, the fretting abrasion resistance and the fretting fatigue resistance can be remarkably improved. The TiB<w>-Ti composite layer can be widely applied to a modification layer and a repair layer of an aircraft engine shell auxiliary part made of a titanium alloy material.

The invention provides a novel nickel alloy. The novel nickel alloy comprises the following components in percentage by weight: 0.001-0.002% of Mg, 0.12-0.14% of Mn, 0.45-0.85% of W, 0.013-0.019% of Co, 0.12-0.18% of Nb, 0.89-0.95% of Sn, 1.3-1.9% of Mo, 1.2-2.4% of Zn, 1.5-2.8% of Ti, 0.51-0.71% of Fe, 1.7-1.9% of Y, 0.73-0.93% of Er, 0.007-0.011% of Sb, 37-45% of Cu and the rest of Ni. The nickel alloy is high-temperature resistant, high in corrosion resistance, low in manufacture cost and high in quality; the service life is greatly prolonged.

The invention discloses alloy powder for die steel laser cladding remanufacturing and a preparation method of the alloy powder. The alloy powder comprises the following components of, in percentage by weight, 0.45%-0.60% of C, 4.20%-8.50% of Co, 3.20%-4.80% of Cr, 1.20%-3.35% of Mo, 0.60%-2.40% of Mn, 0.40%-0.85% of Nb, 0.50%-2.40% of Si, 0.8%-3.2% of B, 0.01%-0.03% of Y2O3, 0.01%-0.03% of La2O3, less than or equal to 0.035% of P, less than or equal to 0.025% of S and the balance Ni. According to the alloy powder for die steel laser cladding remanufacturing and the preparation method of the alloy powder, the crack resistance, the formability, the process stability and the component uniformity of the alloy powder in the laser cladding process can be improved, the high-temperature mechanical property of 4Cr5Mo3V die steel is improved, the service life of the 4Cr5Mo3V steel is prolonged, and the economical efficiency is good.

The invention discloses a high-performance organic silicon resin-polymethyl methacrylate composite material mixed with nanometer silicon nitride for LED package. The composite material is a high-performance material which is formed by polymerization and curing of vinylphenyl silicone oil, hydrogen containing silicon resin, vinyl silicone resin and methyl methacrylate and has the hybrid advantages of organic silicon resin and polymethyl methacrylate; besides, powder formed by compounding nanometer silicon nitride which is mixed in the composite material, surface-treated with a silane coupling agent and wrapped by silica sol, magnesium sulfate whiskers and grapheme is good in compatibility with resin, and high in surface activity, after the powder is uniformly dispersed in the resin, the refractive index, the heat-conducting property, the heat dissipation performance, the high-temperature oxidation resistance, the insulation performance and other performance of the composite material can be improved greatly, and the prepared material is high in mechanical property, long in service life, high in transparency, and excellent in optical performance.

The invention discloses an automotive nylon plastic part processing technology which comprises the following process steps: (1) preparing raw materials; (2) mixing; (3) smelting; (4) molding materials; (5) modifying; (6) crystallizing and separating; and (7) cleaning the surface. The performances of high-temperature oxidation and corrosion resistance are improved, the crystallization rate is high, and the nylon plastic part is easy to mold and process and has the characteristics of high impact resistance and the like.

The invention discloses a high-temperature resistant and abrasion resistant type furnace bottom roller comprising a roller cylinder and roller shafts connected to the two ends of the roller cylinder.Outer threads are arranged at the ends of the roller shafts. Inner thread holes are formed in the two ends of the roller cylinder. The outer threads at the ends of the roller shafts are connected withthe inner thread holes in the ends of the roller cylinder in a threaded mode. The further-improved aspects are that positioning pin shafts radially penetrating through the hole walls of the inner thread holes in the ends of the roller cylinder to be inserted in the ends of the roller shafts are arranged in the connection parts of the inner thread holes in the ends of the roller cylinder and the outer threads at the ends of the roller shafts, and a high-temperature oxidation resistant and abrasion resistant coating is arranged on the surface of the roller cylinder. Assembly or disassembly of the roller cylinder and the roller shafts is convenient and rapid, and high-temperature resistance, oxidation resistance and abrasion resistance are achieved.