Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

3625 results about "Crazing" patented technology

Crazing is the phenomenon that produces a network of fine cracks on the surface of a material, for example in a glaze layer. Crazing frequently precedes fracture in some glassy thermoplastic polymers. As it only takes place under tensile stress, the plane of the crazing corresponds to the stress direction. The effect is visibly distinguishable from other types of fine cracking because the crazing region has different refractive indices from surrounding material. Crazing occurs in regions of high hydrostatic tension, or in regions of very localized yielding, which leads to the formation of interpenetrating microvoids and small fibrils. If an applied tensile load is sufficient, these bridges elongate and break, causing the microvoids to grow and coalesce; as microvoids coalesce, cracks begin to form.

Coated tool of cemented carbide

The principal object of the present invention is to provide a coated cemented carbide tool whose both properties of breakage resistance and wear resistance are improved and whose life is lengthened.The present invention has been made to achieve this object and is related with a coated cemented carbide cutting tool comprising a substrate consisting of a matrix of WC and a binder phase of an iron group metal and a plurality of coated layers provided on a surface of the substrate, in which (a) an innermost layer, adjacent to the substrate, of the coated layers consists essentially of titanium nitride having a thickness of 0.1 to 3 mum, (b) on a mirror-polished cross-sectional microstructure of the said tool, an average crack interval in the coated film on a ridge of a cutting edge and/or rake face is smaller than an average crack interval in the coated layer on a flank face, (c) at least 50% of the cracks in the coated film on the said ridge of the cutting edge and/or rake face have ends of the cracks in the said innermost titanium nitride layer, in a layer above the titanium nitride layer or in an interface between these layers and (d) an average crack length in the coated film on the said ridge of the cutting edge and/or rake face is shorter than an average film thickness on the flank face.According to the present invention, quantitatively specifying the crack intervals and positions of the ends of the cracks in the coated layer results in excellent breakage resistance as well as wear resistance.
Owner:SUMITOMO ELECTRIC IND LTD

Crosslinkable rubber compositions and uses thereof

InactiveUS20030013818A1High crosslinking rateImprove adhesionPolymer scienceCrazing
The crosslinkable rubber composition is crosslinkable at room temperature, has a gelation time at room temperature of 30 days or less, and can prepare a crosslinked rubber sheet by crosslinking the composition at room temperature, wherein the crosslinked rubber sheet has a tensile elongation of 20% or more, and is free of cracks after treatment at 40° C. in a 50 pphm ozone concentration for 96 hr. Specifically, it comprises an ethylene/alpha-olefin/non-conjugated polyene random copolymer rubber comprising a norbornene compound having a specific vinyl end group, an SiH group-containing compound, which has at least two SiH groups in one molecule, and optionally a platinum catalyst, a reaction inhibitor and/or a silane-coupling agent. The sealing, potting and coating materials and adhesives of the present invention comprise the above rubber composition. The rubber composition has a high crosslinking rate at room temperature and excellent productivity, and can prepare crosslinked rubber molded products (including foamed products) having excellent weathering resistance, ozone resistance, heat aging resistance and compression set at low cost. Further, it is suitable for use of electric and electronic parts, transportation machines, civil engineering and construction materials, medical appliances and goods for leisure activities.
Owner:MITSUI CHEM INC

Method for evaluating fatigue life of aged reinforced concrete bridge

ActiveCN105825030AThe prediction method is reasonableGeometric CADForecastingStress concentrationCrazing
The invention discloses a method for evaluating the fatigue life of an aged reinforced concrete bridge. The method comprises the following steps of obtaining initial corrosion time of reinforcement in concrete based on the second diffusion law of Fick, and considering the influence of concrete cracking due to corrosion expansion in a corrosion rate model; adopting a small crack growth and near threshold growth analysis and determining relevant parameters of fatigue crack propagation rate of materials by developing a fatigue crack propagation test of reinforced concrete materials; performing a corrosion fatigue test or finite element analysis on corroded reinforcement to obtain stress concentration factors at different corrosion levels, and integrating into a stress intensity factor model to obtain the fatigue crack propagation rate of the reinforcement under the influence of corrosion; comparing the magnitude of a corrosion pit growth rate and the fatigue crack propagation rate and gradually converting into a single growth analysis on fatigue cracks of the reinforcement; meanwhile, combining with vehicle load observing information to realize life evaluation of a bridge at different service stages. The prediction method disclosed by the invention is reasonable and high in popularization, and can provide technical support for evaluating the life of the concrete bridges.
Owner:CHANGSHA UNIVERSITY OF SCIENCE AND TECHNOLOGY

Centrifugal composite modified indefinite chilled cast iron roller and preparation method thereof

InactiveCN101177759AFine structure of roll bodyEvenly distributedRollsMetal rolling arrangementsCrazingImpurity
The invention relates to a centrifugal combined indefinite chill cast-iron roller and a preparation method thereof, pertaining to steel rolling technical field. The chemical composition of a roll barrel is (weight percent): 3.2-3.8 C, 3.8-4.5 Ni, 1.2-1.8 Cr, 0.2-0.4 Mo, 0.2-0.5Cu, 1.0-1.8 Si, <0.8Mn, 0.10-0.30 Nb, 0.05-0.20 V, 0.05-0.20 Ti, 0.04-0.07Mg, 0.02-0.05 Y, 0.01-0.03 Sb, and the rest are Fe and unavoidable microimpurity. The invention employs a electric stove to produce a roller, and the roller is moulded with centrifugal casting method; the roller is characterized by high strength and hardness, good toughness, hardness uniformity and hardenability, excellent wear resistance and oxidation resistance and the anti-cold shock and heat shock properties are also good; no phenomena like breaking, peeling, crazing and steel sticking are in the operation process; the service performance is apparently better than high nickel-chrome indefinite chill cast-iron roller; the processing technique is simple, high-heat treatment is not needed and the production cost is low. The invented roll has the advantages that: the rolling mill operating rate is significantly improved, the production cost of mill bar is reduced, the surface quality of the mill bar is improved and the economic and social benefits are good.
Owner:BEIJING UNIV OF TECH

Nickel-based welding electrode for welding nickel-chromium-molybdenum alloy

The invention relates to a nickel-based welding electrode which comprises the following component by weight percent (wt%): 50.0-68.0% of Ni, 18.0-23.0% of Cr, 6.0-11.0% of Mo, 3.0-6.0% of Nb, 2.50-9.00% of Fe, 0.01-0.1% of C, 0.10-1.00% of Mn, 0.010-0.10% of Si, 0.015% of S or less, 0.015% of P or less, 0.01-0.10% of Cu, 0.003-0.010% of Co and the balance of impurities. The coat of the nickel-based welding electrode comprises the following components by weight percent of the welding core: 12-18% of marble, 10-15% of fluorite, 12-18% of barium carbonate, 5.0-6.4% of rutile, 3.5-5.0% of ferroniobium, 3.3-4.5 of chromium metal powder, 0.45-0.65% of sodium carbonate, 0.45-0.65% of electrolytic manganese and 1.3-1.8% of zircon sand, and the adhesion agent is 10-20% of the total weight of the power. The nickel-based welding electrode is prepared by mixing, wrapping mixture on the welding core and baking at low and high temperature. The nickel-based welding electrode disclosed by the invention is used for nickel-chromium-molybdenum alloy steel welding, ensures that the excellent mechanical properties, the excellent corrosion resistance, the excellent thermal crack resistance and the hightensile strength of the welding seam match with those of the base material, has good welding process performance, guarantees attractive molding and can be used for the welding of the steel (with 9% of Ni) working at low temperature.
Owner:ATLANTIC CHINA WELDING CONSUMABLES

Welding repair method for large-sized heat-resistant steel castings

The invention relates to a welding repair method for large-sized heat-resistant steel castings, and solves the problems that the welding stress is difficultly removed, the defects of incomplete fusion, incomplete penetration, delayed crack and slag inclusion are easily caused in a repair process and the repair quality is difficultly guaranteed as the heat-resistant steel castings are poorer in welding performance, complicated in defect position and large in workpiece in an existing manual arc welding type surfacing welding mode for repairing large-sized castings. The method mainly comprises the following steps: 1, removing the defects; 2, performing heat treatment; 3, performing dye check; 4, performing statistics on the repair welding quantity; 5, preheating before welding; 6, performing repair welding on defect parts; 7, cleaning and repairing; 8, performing post-welding heat treatment; 9, performing nondestructive inspection. According to the method, the large-area defects of the castings can be effectively repaired, the repair quality is guaranteed, the processing and use requirements of the castings can be met after repair, and the economic loss of scrapped important or major castings is reduced. The method is used for repairing the large-area defects of the large-sized heat-resistant steel castings.
Owner:HARBIN JIANCHENG GRP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products