239results about How to "Reduce shrinkage stress" patented technology

The invention relates to a ceramic composite for 3D printing and a preparation method thereof. The ceramic composite for 3D printing is characterized by comprising the following components according to parts by weight: 20-45 parts of acrylate monomer, 121-165 parts of ceramic powder, 10-20 parts of spiro-orthocarbonate expansive monomer, 2-14 parts of a dispersant, 1-3 parts of a photo-initiator, 0-3 parts of a photo-inhibitor, and 1-3 parts of an ultraviolet absorber. The ceramic composite for 3D printing is low in curing and contraction degree and short in curing time and therefore is applicable to investment casting.

The present invention discloses an anti-sagging spraying primer coat, which comprises, by weight, 10-25% of a two functionality aliphatic polyurethane acrylate, 20-30% of a modified epoxy acrylate, 10-20% of a polyester acrylate, 10-15% of a monomer, 25-30% of a filler, 3-5% of a photoinitiator, 0.5-2% of an anti-sagging additive, 0.2-0.5% of an anti-foaming agent, and 0.1-0.3% of a leveling agent. With application of the UV paint as the spraying primer coat, the problem of sagging during a coating process can be avoided, the whole coating efficiency can be improved, the environment-friendly characteristic is provided, and the organic solvent emission can be reduced.

The invention provides methods of reducing shrinkage stress in cross-linked polymerized materials by combining an addition-fragmentation chain transfer additive with a resin system prior to polymerization. The methods of the invention can improve the performance of conventional resin systems by reducing the shrinkage stress without significantly degrading the mechanical properties of the polymerized material. The shrinkage stress in the crosslinked polymeric materials produced by the methods of the invention may be from 25% to 75% of that of a control material produced by polymerization of the resin system alone to the same conversion.

The invention discloses a polyurea adhesive composition and a preparation method thereof. The polyurea adhesive composition is mainly prepared from polyaspartic ester, nanofiller and a curing agent. The polyaspartic ester is prepared by enabling an organic diamine compound and maleate to make a Michael addition reaction; the curing agent is prepared from an organic diisocyanate or polyisocyanate component, and can be a monomer, a polymer, a derivative of isocyanate, a prepolymer or a semi-prepolymer; the nanofiller is selected from nano-silicon dioxide, nano-titanium dioxide and nano-silicon carbide. By utilizing the Michael addition reaction of the organic diamine compound and the maleate, primary amine is transformed into secondary amine on the one hand, and a group having higher steric hindrance is introduced on the other hand, so that the defects that a polyurea material is rapid in reaction time and short in gelation time are overcome; the nanofiller is added into the polyurea adhesive composition, so that the stress shrinkage caused during the curing of an adhesive film is effectively reduced, and the polyurea adhesive composition is high in bonding strength.

The invention discloses a double-layer thermal barrier/high-temperature low-infrared emissivity integrated coating which is of a multilayer superposition structure. The multilayer superposition structure sequentially comprises a metal bonding layer, a thermal barrier ceramic inner layer, a thermal barrier ceramic outer layer and a low-infrared emissivity layer from inside to outside, and the thermal barrier ceramic inner layer is La2Zr2O7-8YSZ mixture layer, wherein the mass fraction of La2Zr2O7 powder in the mixture is not more than 45%, the thermal barrier ceramic outer layer is a rare earthzirconate layer, and the low-infrared emissivity layer is a Bi2O3-Al2O3-ZrO2-CaO-SiO2 glass coating comprising conductive phase AuPt alloy powder. The invention also provides a metal composite material with the coating and a preparation method thereof. The integrated coating has the characteristics of heat insulation performance, high-temperature low infrared emissivity, excellent thermal shock resistance and the like.

The present invention provides a method for modifying a surface of a polymer derived from a mixture comprising a thiol monomer and an olefinic monomer. The method comprises exposing at least a portion of the polymer surface to electromagnetic radiation of sufficient energy to modify the polymer surface. The present invention also provides a polymer derived from polymerizing a mixture of monomers comprising a thiol monomer, an olefinic monomer, and an iniferter.

The invention discloses a bicomponent water-based nano waterproof coating and a preparation method thereof. The bicomponent water-based nano waterproof coating is prepared by mixing a component A and a component B, wherein the component A comprises the following ingredients in parts by weight: 35-37 parts of nano styrene-butadiene rubber, 37-39 parts of nano waterproof emulsion, 22.9-26.7 parts of deionized water, 0.5-0.7 part of a nano silicon auxiliary agent, 0.2-0.4 part of a defoaming agent and 0.2-0.4 part of a preservative; and the component B comprises the following ingredients in parts by weight: 54-56 parts of cement, 26-30 parts of ground calcium carbonate powder, and 16-18 parts of quartz powder. When the bicomponent water-based nano waterproof coating is used, the component A and the component B are mixed and stirred uniformly with each other according to a ratio of the component A to the component B of 1:(1.0-1.2). By using the bicomponent water-based nano waterproof coating, while the waterproof performance is implemented, the contraction stress of a waterproof coating layer during drying can also be reduced, thereby effectively improving or putting an end to the problem that a brick pasted on the waterproof coating layer generates bellowing and falling off. The construction method of the bicomponent water-based nano waterproof coating is consistent with that of a common polymer cement waterproof coating, and the product is environmentally friendly and nontoxic.

Hot cracking in laser welds produced in metal workpieces, especially aluminum or magnesium sheet alloys, is avoided by suitably combining the beams of two different lasers, for example a CO₂ laser and a YAG laser, into a compound beam that is moved along a weld path in the surface of the workpiece. The power level of at least one of the lasers is cyclically varied so that weld nugget segments of different alternating, hot crack free, configurations are produced in a linear weld.

The invention discloses a large and medium chinaware manufacturing method. Compared with a traditional method, such subsequent treatment processes as outer surface finishing, finish carving treatmentand/or colored drawing treatment and glazing of large and medium chinaware ceramic blanks and production of chinaware outer profile surfaces belong to simultaneous asynchronous treatment spaced by specific space-time intervals, so that the problem of performing subsequent processes one by one after completion of previous treatment procedures in the traditional method is overcome, and saving of a lot of time and delication of the artistic effect can be both considered. In addition, the method can finish complex shapes, is more suitable for manufacturing of large and medium artistic shape chinaware, meanwhile, greatly enriches the shaping range of large and medium chinaware, and greatly reduces the manufacturing cost of large artistic porcelains.

The invention relates to a forming method of a block-shaped amorphous composite material, which is characterized by comprising the following steps: (1) selecting a block-shaped amorphous composite material which has the component purity greater than 99.3% and substrate components with strong glass forming capacity, preparing a high-purity block-shaped amorphous composite material, and cutting the block-shaped amorphous composite material into an ingot blank according to a forming part; (2) heating the ingot blank under gas protection at the speed of 0.5-50 DEG C/s to the liquidus temperature and the solidus temperature range of the block-shaped amorphous composite material, and insulating for 3-30 minutes; and (3) under pressure, filling a liquid-solid coexistent metal slurryinto a mold cavity at a deformation rate of 102-106s<-1>, and forcibly cooling for solidifying at the cooling speed of 1-200 DEG C/s while maintaining the pressure. The invention can obtain the metal slurry the second phase of which is uniformly distributed in the liquid phase, has low forming temperature, long service life of the mold and high production efficiency, improves the product performance, can be used for forming parts with complex forming shapes and thin walls, and can be widely applied to amorphous composite materials of Zr-series, Cu-series, Ti-series, La-series, Co-series and the like.

The invention discloses highly anti-bending and wearing-resistant lightweight concrete, which comprises the following raw material constituents in parts by weight: 200-250 parts of cement, 100-150 parts of coal ash, 150-200 parts of river sand, 100-180 parts of manganese residue, 150-200 parts of ceramsite, 20-50 parts of silicon carbide, 15-35 parts of plant fiber, 200-250 parts of water, 0.3-1.5 parts of dipropyl ethylene glycol monobutyl ether, 3-6 parts of silicon resin polyether emulsion, 0.3-1.8 parts of sodium chloride, 2-5 parts of triethanolamine, 0.3-1 part of sodium sulfate, 1-3 parts of epoxy resin, 1-3.5 parts of waste polyurethane, 1-2.3 parts of sodium stearate, 5-16 parts of nano calcium oxide, 0.3-0.9 part of coagulant, 2-5 parts of melamine water reducer and 5-18 parts of foaming agent. The highly anti-bending and wearing-resistant lightweight concrete provided by the invention has high anti-bending strength, good wear resistance, light weight and excellent water resistance.

A fluororesin tube 30 of the present invention has a tensile strength of 80 N/mm² or more in both of the circumferential direction and the axial direction. The fluororesin tube 30 is produced by winding with two or more turn of a fluororesin film 20 having a thickness T of 2.5 μm or less (particularly 2.0 μm or less) to form a lamination. At least an outermost layer of the tube is fused to a layer immediately thereunder and a rising height H of the fluororesin film at the end-of-winding side 21 is always 0.1 μm or more and 2.0 μm or less when measured at any position of the side 21. A level difference D of the end-of-winding side 21 of the fluororesin tube is preferably more than or equal to sum of the film thickness T and 0.1 μm, and less than or equal to 3.0 μm (particularly 2.3 μm) when measured at any position of the side 21.

The invention discloses low-ultraviolet energy curing vacuum-spraying UV coating and a preparation method thereof. The low-ultraviolet energy curing vacuum-sprarying UV coating is made of, by weight, 26-35% of modified low-viscosity high-functionality epoxy acrylate, 10-25% of modified high-functionality polyester acrylate, 8-12% of special modified polyurethane acrylate, 25-40% of TPGDA, 3-7% of HEMA, 0.3-0.8% of wetting dispersant, 5-10% of transparent filler, 4-8% of photoinitiator, 0.3-0.5% of leveling agent, and 0.1-0.3% of other auxiliaries. Compared with common like coatings, the vacuum-spraying UV coating has the advantages that ultraviolet energy required for coating curing is greatly reduced, and energy is saved and effectively used. In addition, possibility to cause quality defect of the backlight side of special-shaped workpieces is decreased. The vacuum-spraying UV coating has the advantages of excellent coating strength and transient leveling property.