41results about How to "Less metallurgical defects" patented technology

The invention discloses a special aluminum-manganese alloy powder formula for 3D printing, a preparation method and a printing method thereof, wherein the alloy powder is a pre-alloy, and in terms of mass percentage, it includes: Mn: 1.0-5.5wt%; Sc : 0.3~0.6wt%; Zr: 0.1~0.3wt%; Mg: 0.8~1.2wt%; Si: 0.2~0.25wt%; Fe: 0.2~0.25wt%, Cu: 0.1~0.2wt%; Zn: 0.1 ~0.2wt%, the rest is Al. The parts of the Al-Mn alloy composition of the present invention after laser 3D printing have no cracks, high density, corrosion resistance, high mechanical properties, and low anisotropy; it solves the problem that the traditional casting and forging Al-Mn alloy composition can be directly used in 3D printing The problem of easy cracking and low mechanical properties. After the alloy composition of the invention is 3D printed, the tensile strength is higher than that of the traditional cast and forged aluminum-manganese alloy. At the same time, compared with other mature 3D printing Al-Si alloys, the alloy of the present invention has higher corrosion resistance and mechanical properties.

The invention discloses a special Al-Cr heat-resistant alloy powder for 3D printing, a preparation method, an application and an Al-Cr heat-resistant alloy. The Al-Cr heat-resistant alloy powder is a pre-alloyed powder, which includes Cr : 3~4.5%, Mg: 0.5~1.2%, Mn: 0.3~0.5%, Sc: 0.3~0.8%, Zr: 0.1~0.4%, Si: 0.05~0.55%, and the rest is Al; the 3D printing The special Al-Cr heat-resistant alloy powder is screened and dried; after the drying process, the coaxial powder feeding 3D printing is carried out. The density of the Al-Cr heat-resistant alloy obtained by the present invention exceeds 99%, and the average hardness reaches 150HV 0.2 , The tensile strength at 200 ° C is nearly 300Mpa, the structure is fine and uniform, the density is high, the anisotropy is low, and it has excellent room temperature performance and high temperature performance.

The invention relates to a laser cladding powder for 30CrMnSiNi2A steel and a preparation method. The amount of each component in the laser cladding powder is Cr 0.8%-1.0%, Mn 0.75%-1.10%, Si 0.65% by weight percentage ‑1.10%, Ni2.0%‑3.2%, C0.16%‑0.22%, Cu0.15%‑0.20%, P0.015%‑0.020%, S0.01%‑0.015%, Rare earth 0.001%‑0.015% , the remainder is iron. The present invention further proposes a preparation method of the cladding powder. The laser cladding powder is specially used in the laser cladding technology of 30CrMnSiNi2A steel, so as to ensure the excellent bonding strength of the cladding interface, lower metallurgical defects and reduced dilution rate, and improve the fusion rate. The toughness of the cladding layer improves the wettability of the cladding powder, inhibits the cracking of the cladding layer and delays the crack growth rate.

The invention discloses a process method, in particular a process method for reducing metallurgical defects of a GH4169 nickel-based alloy ingot, and belongs to the technical field of nickel-based alloy remelting production technology. Provided is a process method for reducing metallurgical defects of GH4169 nickel-based alloy ingots with few finished product quality defects. The process method uses the GH4169 nickel-based alloy smelting ingot obtained by vacuum induction melting as the base ingot, and obtains reduction of the metallurgical defects of the GH4169 nickel-based alloy ingot through one homogenization treatment, one quick forging upsetting and one remelting.

The present invention discloses an aluminum alloy evaporator inner wall thin plate and a continuous casting rolling production process thereof. The thin plate adopts an aluminum manganese alloy as a base, contains silicon, iron, copper, manganese, magnesium, zinc and titanium, and is prepared by adopting a continuous casting rolling production process. The process comprises the following steps: adding raw materials to a smelting furnace to carry out melting, refining, and residue removing; discharging the resulting material to a cast rolling machine from the furnace to carry out cast rolling; carrying out a first annealing treatment on the cast-rolled plate material to reduce needle-like FeAl3 and influence on mechanical property by a phase composition, wherein the phase composition and the Al-Mn solid solution achieve phase equilibrium; carrying out cold rolling on the first-annealed plate material 5-6 times; carrying out a second annealing treatment on the cold-rolled plate material; and carrying out foil rolling 1-2 times to prepare the aluminum alloy evaporator inner wall thin plate. The technical scheme of the present invention has the following characteristics that: good moldability, good weldability, and good corrosion resistance are provided, structure and performances are uniform, metallurgical defects are less, anisotropy is low, strength is high strength, elasticity is good, and the like.

The invention discloses a powder metallurgy preparation method of nanophase / metal composite powder and a block material thereof. The method comprises the steps of carrying out low-speed ball milling on nanophase powder and metal powder for a long time, and uniformly dispersing nanophases on the surface or inside the flake metal powder, so as to obtain nanophase / metal flake composite powder; and carrying out high-speed ball milling for a short time to weld the nanophase / metal flake composite powder to obtain nanophase / metal granular composite powder. According to the preparation method, the problems of uniform dispersion and interface bonding of the nanophases in a metal matrix can be solved through only adjusting the speed of ball milling; compared with traditional constant-speed ball milling, the ball milling method has the advantages that dispersion of the nanophases is more uniform, the interface bonding strength is higher, and the prepared material is more excellent in performance; and the preparation method is simple and efficient in technology and applicable to batch preparation.

The invention discloses a manufacturing method, in particular discloses a manufacturing method for a GH4169 nickel-based alloy ingot with low metallurgical defects, and belongs to the technical field of nickel-based alloy remelting production technology. Provided is a method for manufacturing a GH4169 nickel-based alloy ingot with low metallurgical defects, which can significantly reduce the metallurgical defects of the GH4169 nickel-based alloy ingot. The manufacturing method uses the GH4169 nickel-based alloy ingot obtained by vacuum induction melting as the base ingot, and obtains the GH4169 nickel-based alloy ingot with low metallurgical defects through two remelting, one homogenization treatment and one rapid forging and drawing, wherein, The sequence of the homogenization treatment and the rapid forging and drawing process is arranged between two remelting processes.

The invention relates to the field of aeroengines and gasoline turbines, in particular to a technological method of a high-efficient machining swirler for an aeroengine. The method comprises a step ofpreparing a swirler blank, wherein the swirler blank is manufactured by columnar forging pieces, and the columnar forging pieces are manufactured by aviation materials; the method also comprises a step of preparing a swirler semi-finished product and a step of gripping and repairing; the step of preparing a swirler semi-finished product comprises the following steps: turning the swirler semi-finished product at least one time and milling the swirler semi-finished product at least one time so as to prepare the swirler semi-finished product; and the step of gripping and repairing comprises thefollowing steps: trimming a profile surface of the swirler semi-finished product according to a finished product requirement of the aeroengine so as to prepare a swirler finished product. By adoptinga matched machining way of turning and milling, a machining period is shortened; and by matching with a gripping and repairing operation, a finished product ratio is increased, so that the manufactured swirler finished product has the advantages of stable metal quality and longer service life, and the manufactured swirler finished product meets a high-standard requirement on the aeroengine.

The invention discloses a preparation process of a nickel-based superalloy with high content of refractory elements, and belongs to the technical field of alloy preparation. The process adopts vacuum induction melting (VIM) + electroslag remelting (ESR) process to prepare alloys with high content of refractory elements. During vacuum induction melting, by controlling the feeding method, increasing the refining temperature and prolonging the refining time, and accelerating the solidification rate, etc., the segregation of refractory metals and low-density alloy elements can be effectively suppressed, and the composition uniformity of the upper and lower parts of the master alloy ingot can be improved. Electroslag remelting eliminates secondary shrinkage cavities in alloy ingots and reduces impurity content to improve metallurgical quality. The invention can not only significantly reduce the micro-segregation and macro-segregation of high-content refractory elements, but also effectively reduce the content of harmful gas elements such as O and N in superalloys, thereby improving the purity of the alloy and reducing the degree of segregation of high-density elements. Improve the heredity of the abnormal structure of the alloy and improve the comprehensive mechanical properties of the alloy.

The invention provides a technique for producing precision castings of zirconium pump and valves. The technique is characterized in that the precision castings of zirconium pumps and valves are produced by adopting the methods of lost-wax ceramic-shell precision casting and hot isostatic pressing, wherein the lost-wax ceramic-shell precision casting refers to near-net-shape casting adopting a lost-wax ceramic shell for casting in a vacuum self-consuming skull furnace; the lost-wax ceramic shell is formed through reproduction according to a wax pattern consistent with the geometric shape and size of a pump and valve component; the first two layers of the shell of the inner surface of the lost-wax ceramic shell is made from special oxide; the whole shell is manufactured through the process links of wax pressing, painting, shell hanging, dewaxing, roasting and the like; and the hot isostatic pressing is to place a to-be-treated casting in a container which ishermetic and resistant to high pressure and can be heated to high temperature, vacuumize the container, fill the container with high-pressure inert gas and heat the container to a preset temperature. The technique has the advantage of solving the problem of low material utilization rate and hidden trouble caused by no welding seams at high temperature and high isostatic pressure in all directions, high surface finish of the casting, few internal defects of the casting, pure composition and stable performance.

The invention discloses a preparation method for high-purity titanium nickel copper shape memory alloy ingots, and relates to the technical field of shape memory alloy preparation. Raw materials are screened, cleaned and dried; the raw materials comprise sponge titanium particles, electrolytic nickel particles, high-purity copper particles and phosphorus copper intermediate alloys; after the driedraw materials are weighed, the materials are paved in a smelting furnace in sequence according to a first preset condition; the materials are smelted according to a vacuum induction smelting technology, wherein the smelting process comprises power supply, degassing, refining and casting; the aftertreatment is performed on ingots after casting according to a second preset condition by adopting a hot isostatic pressing method; and then, the flaw detection, the riser cutting and the bottom cushioning are performed on the ingots after aftertreatment in sequence to obtain high-purity titanium nickel copper ingots. The preparation method achieves the technical effects of convenience to prepare the ingots, controllable and lower content of impurity element O, high content stability of the O element, fine grain structure and great reduction of metallurgy defects.

The invention discloses a neodymium-iron-boron permanent magnet material, a preparation method and a magnetic field auxiliary direct casting device. A main magnet of the device is a circular-ring-shaped magnet which is magnetized in a radial mode. A first disc-shaped repulsion magnet with the magnetic field direction being axially upward is arranged below the center of the main magnet, and a second disc-shaped repulsion magnet which is magnetized in a radial mode is arranged on the periphery of the first repulsion magnet. A regulating magnet is arranged at the upper end of the main magnet, second soft iron is arranged on the upper portion of the regulating magnet, first soft iron is arranged outside the regulating magnet, and a circular-ring-shaped magnet guide magnet which is magnetized downwards in the axial direction is arranged outside the main magnet. The chemical general formula of the neodymium-iron-boron permanent magnet material is [Nd (85-x-y) CoxFeyAlzB (15-z)] (100-a) Ma, wherein in the formula, x+y is larger than or equal to 30 and smaller than or equal to 70, z is larger than or equal to 0 and smaller than or equal to 10, and a is smaller than and equal to 4. Compared with a material prepared without adding magnetic fields, the performance of the neodymium-iron-boron permanent magnet material is greatly improved, the preparation process is simple, cost is low, products are dense, and the neodymium-iron-boron permanent magnet material is suitable for industrial production.