78results about How to "Reduce crack formation" patented technology

A composite cement material is prepared from cement material and carbon nanotubes, wherein the carbon nanotubes are present from about 0.02 wt % to about 0.10 wt % based on weight of cement material. The process for preparing such cement compositions includes sonicating a mixture of a surfactant, water, and carbon nanotubes; and blending the dispersion and the cement material to form a cementitious paste. The process may also include curing the cementitious paste. The composite cement materials are useful in a variety of cement applications where a reduction in nanoscale flaws and fractures is desired.

Provided are a gradient wear-resistant coating and a method for preparing the same. Co50+0.15% CeO2 powder, Co50+0.25% CeO2+6% Ni/Wc powder and Co50+0.4% CeO2+12% Ni/WC powder are used for preparing the gradient wear-resistant coating with the structure of a bottom layer, a transition layer and a wear-resistant layer on the surface of a workpiece in a coaxial powder supply manner and a laser cladding manner, and the wear resisting performance of the work surface of a part is improved. An ultrasonic vibration device and a contour tracing electromagnetic induction heating device are adopted in the cladding process. Ultrasonic oscillation of a certain degree is applied to the area close to a cladded area of the workpiece, the grain size of a cladding layer can be remarkably refined, residual stress can be remarkably eliminated, and therefore generated cracks are reduced, and a cladding layer structure with good performance is obtained. The contour tracing electromagnetic induction heating device can be utilized for effectively reducing thermal stress brought by the temperature gradient of the cladding layer and relieving the cracking tendency. According to the technological parameters of the ultrasonic vibration device, the work frequency ranges from 10 kHz to 20 kHz, the maximum output power is 1,000 W, and the pneumatic pressure ranges from 0.3 MPa to 0.6 MPa. According to the technological parameters of the contour tracing electromagnetic induction heating device, the voltage is 380 V, the frequency is 60 Hz, and the heating temperature ranges from 150 DEG C to 1,000 DEG C.

The invention relates to a connection comprising at least two components having the following features: a first component and a second component, of which at least the second component comprises reinforced plastic, a self-piercing connection element (30) having a head and a shaft, the head thereof being supported on the first component and the shaft thereof running completely through the first and the second component, and a disc-shaped counter bearing to which the shaft is fastened such that the at least two components are fastened between the head and the counter bearing. The invention further relates to a method for the production of said connection.

Disclosed is a method of making a conductive material or active material that includes graphene or other 2-D materials. The method includes obtaining a layered stack. The layered stack including one or more conductive materials or 2-D materials separated by a metal layer, and one or more substrate materials. The stack can be subjected to a metal removal process to obtain two conductive or active materials. A first conductive or active material can include a first substrate layer attached to the first active layer. The second conductive or active material can include a second substrate layer attached to the second active layer. The first and second active layers can be conductive graphene layers.

The invention relates to a method for preparing a WC hard alloy wear resistance area on a petroleum drill rod surface. The method is characterized in that: the method comprises the following steps: (1) carrying out a pretreatment for the petroleum drill rod surface; (2) selecting alloy powder and adjusting an automatic powder feeding device; (3) cladding a bottoming alloy coating by a high power laser; (4) cladding spherical WC and Ni-Cr-B-Si mixed alloy powder by the high-power laser; (5) carrying out defectoscopy inspection after cladding. According to the present invention, the gradient coating method is adopted to prepare the WC hard alloy wear resistance area on the petroleum drill rod surface, the nickel-base alloy powder is adopted as the bottoming layer, the high wear resistance WC hard alloy powder is adopted as the working layer, such that the good binding strength of the working layer and the substrate is ensured in the case of meeting of the working layer characteristics, and the cracks can be prevented from expanding to the substrate during the using process, wherein the nickel-base alloy powder has good toughness and high strength, and has good metallurgy compatibility with the substrate.

A method of preparing a building material is provided. An aggregate material, water, a hydraulic binder material, and one or more hydraulic activators are mixed. The hydraulic binder material comprises slag material. The mixture is allowed to harden. A building material is also provided. The building material includes a slag material, and one or more hydraulic activators.

The invention concerns a device for stiffening a flat component, a process for the production of a flat component, in particular a fiber composite component, and a fiber composite component. The device has a portion for producing a space for receiving a mold core for the transmission of a pressure for pressing the flat component and the device. It is characterised by means for positively lockingly and/or frictionally lockingly positioning the mold core in the space of the device. The process according to the invention includes the following steps: introducing the mold core into the portion of the device, positively lockingly and/or frictionally lockingly positioning the mold core in the portion of the device by means of the means, applying the device including the mold core to the non-hardened material layer or layers, pressing the material layers, and hardening the material layer or layers and joining the device to the material layer or layers.

The invention discloses a method for preparing a WC (Wolfram Carbide) cemented carbide wearing layer on a surface of a petroleum drilling tool stabilizer through laser cladding. A tough bottoming transition layer which is in good metallurgical bonding with a matrix is formed on the surface of a shell in a fusion covering manner through rapid laser scanning by using a high-power laser, and mixture alloy powder of spherical WC and Ni-Cr-B-Si, which is wearing-resisting and excellent in corrosion resistance, is prepared on the surface of the bottoming alloy through laser cladding. The power, position, shape and the like of a laser beam of the method can be accurately controlled, selective area or even micro-area fusion covering is easy to realize, the dilution rate of coating components is low, the coating thickness can be accurately controlled, non-contact type treatment is adopted, and automatic control is easy to realize in the whole process; in addition, a laser cladding process is non-pollution on the environment, free of radiation and low in noise, has the characteristics that the productivity is high, the energy consumption is low, the cladding layer machining margin is small, the finished product rate is high, the comprehensive cost is low, and the like, and can be widely applied.

An additional fiber reinforced layer reduces crack propagation in a lightweight structure of an outer skin adhesively bonded to a reinforcing frame. For this purpose the additional fiber reinforced layer is interposed between the outer skin and the frame and adhesively bonded to the outer skin and to the frame. The additional layer has reinforcing fibers extending in parallel to each other or the reinforcing fibers are woven into a fabric embedded in a synthetic adhesive bonding material. The embedding of the parallel fibers or of the fiber fabric in the bonding material is performed either prior to the bonding or during the bonding of the additional layer to the outer skin and to the reinforcing frame.

An elastomer joint, in particular for chassis parts of motor vehicles, comprising a housing (6), an elastomer body (2) arranged in the housing (6), and a joint body (1) that is arranged in the elastomer body (2), is characterized in that the housing (6) has a cylindrical inner wall, and a spacer (4) is provided that is arranged at an axial end of the elastomer body (2) between the latter and the inner wall.

In a material-interlocking connection between aluminum and copper in a layer assembly comprising an aluminum layer disposed on a copper element and a copper layer disposed on the aluminum layer, a weld seam is formed on the top copper layer so as to form a weld which extends through to top copper layer and the aluminum layer into the copper element so as to form in the weld seam an alloy of copper and aluminum.

The invention relates to a ramming material for a ladle lining and a preparation method thereof. The ramming material comprises the following raw materials: 52 to 57 percent of silica, 20 to 23 percent of high-alumina bauxite, 5 to 10 percent of clay, 5 to 15 percent of graphite, 0.1 to 5 percent of fly ash, 0.2 to 5 percent of silicon carbide power, 0.1 to 3 percent of chromium slag powder, 0.1 to 1 percent of sodium silicate and 0.1 to 1 percent of aluminum polyphosphate. Advantages of the invention are as follow: as that structure strength is high in the use process, it will not cause ladleleakage accidents due to loosening, peeling and other damages in the use process, thus ensuring the safety of people and equipment around the ladle during lifting and transporting, preventing molteniron from sticking to the ladle, preventing wrapping of molten iron in slag, improving the recovery rate of molten iron, and greatly improving the safety and economy.

The invention relates to a heat shield element for lining a combustion chamber wall, to a combustion chamber and to a gas turbine. The heat shield element comprises a hot side that can be exposed to a hot medium, a wall side opposite said hot side, and a peripheral side adjoining the hot side and the wall side and having a peripheral side surface. Relief slots are introduced into the material in an area of the heat shield element that is susceptible to material cracks induced by thermal stress, thereby limiting crack propagation.

A process for preparing curable oligomeric and/or polymeric polysilazanes comprises (a) forming at least one dihalosilane-base adduct by reacting at least one dihalosilane with at least one base; (b) optionally, combining at least one dihalosilane-base adduct and at least one organodihalosilane; and (c) carrying out ammonolysis of at least one dihalosilane-base adduct or of the resulting combination of at least one dihalosilane-base adduct and at least one organodihalosilane; with the proviso that the base (1) is used for the dihalosilane-base adduct formation in a limited amount that is less than or equal to twice the stoichiometric amount of silicon-halogen bonds in the dihalosilane or (2) is used for the dihalosilane-base adduct formation in excess of this limited amount and, prior to the ammonolysis, the total amount of the resulting reacted and unreacted base is reduced to no more than this limited amount.

A zirconium-based alloy, suitable for use in a corrosive environment, where it is subjected to increased radiation and comprises 0.5-1.6 percentage by weight Nb and 0.3-0.6 percentage by weight Fe. The alloy is characterised in that it comprises 0.5-0.85 percentage by weight Sn.

The invention discloses a laser additive manufacturing method of an iron nickel-manganese copper dissimilar material metal part. The method comprises the following steps that firstly, an iron-nickel alloy is deposited on a substrate by adopting a laser additive manufacturing method; secondly, mixed powder composed of iron-nickel alloy powder with the iron-nickel alloy powder mass content larger than 70% or smaller than 50% and manganese-copper alloy powder serves as a raw material, and an iron nickel-manganese copper transition area is formed through deposition with the laser additive manufacturing method; and thirdly, manganese-copper alloy is deposited on the iron nickel-manganese copper transition area through the laser additive manufacturing method, the substrate is removed, and the iron nickel-manganese copper dissimilar material metal part is obtained. According to the method, by adjusting the deposition direction and controlling the transition path of the mixed powder, the defects of cracking, undissolved particles and the like of the iron nickel-manganese copper gradient material are overcome, and the obtained iron nickel-manganese copper dissimilar material metal part is compact in structure and small in transition area size, has the damping performance and low expansion performance and is wide in application range.

The embodiments disclose a silicon substrate with a group III-V material and a method for fabricating a group III-V material on a silicon substrate. The method involves providing a silicon substrate. A first layer formed atop the silicon substrate, is subsequently patterned to expose the underlying silicon substrate. A group III-V material layer is formed over the patterned first layer and also on the exposed silicon substrate. The group III-V material layer is subjected to chemical mechanical polishing (CMP) to expose the first layer resulting in the formation of a plurality of areas suitable for growing a device layer on the silicon substrate.

The invention relates to the field of laser cladding materials, and discloses nickel-based multi-component laser cladding powder. The powder comprises, by mass, 10-25% of Fe, 6-15% of Al, 1-5% of TiB2, 0.5-1.0% of Dy and the balance Ni. The invention further discloses a laser cladding method for the powder. The method comprises the steps that the nickel-based multi-component laser cladding powder and absolute ethyl alcohol are mixed, the surface of a cladding base material is evenly covered with the mixture, drying is carried out after roll pressing, a preformed layer is formed, and the cladding layer can be obtained through laser cladding. By means of the technology, the crack-free laser cladding layer can be obtained, the hardness is high, the cost is low, the fusion degree is improved, the strength and plasticity are ensured, and the powder is suitable for repair machining of various parts.

The invention relates to a method in connection with a change process of a reel-up of a fibre-web machine, which method is applied when performing a change of reeling of a web (W) from a web roll (11) being completed to a new web roll for reeling the next roll around a reeling shaft (12). In the method, for fastening the surface layer/surface layers of the web roll (11) to the web roll (11) beingcompleted, at least one two-sided tape (20) is adhered from its one side to the web (W) being passed to the web roll (11) being completed or to the surface of the web roll (11) and said tape (20) is adhered from its other side to the surface of the web roll (11) being completed/to the surface of the web (W) being reeled onto the web roll (11) being completed due to the effect of a reeling nip between the reel drum (13) and the web roll (11) or a pressing-roll nip between the web roll (11) and a pressing roll (14) or due to the effect of the tightness (T) of the web.

The present invention aims to provide a resin composition containing a cyanate ester compound which can reduce the formation of carbamate compounds so that the resin composition can be suitably used as an sealing material. The present invention relates to a curable resin composition containing a cyanate ester compound and a dehydrating agent.