The invention provides a flexible heat conduction sheet. The flexible heat conduction sheet is prepared by the following steps of mixing the following raw materials in parts by mass, calendering, primarily curing, coiling, curing at high temperature, and slicing. The flexible heat conduction sheet is prepared from the following raw materials in parts by mass: 80 to 90 parts of vinyl polysiloxane,10 to 20 parts of toughening agent, 1.2 to 1.5 parts of hydrogen-containing polysiloxane, 0.01 to 0.2 part of platinum catalyst, 0.001 to 0.01 part of inhibitor, 100 to 200 parts of carbon fiber, 5 parts of vapor-phase white carbon black, and 170 to 200 parts of one or multiple of aluminum oxide, zinc oxide, silicon carbide, aluminum powder, boron nitride and aluminum nitride.

Flexible heat conduction sheet and preparation method thereof

The invention provides a composite conductive plastic, which is prepared from the following raw materials: 20wt%-40wt% of conductive filler; 55wt%-75wt% of main plastic; 0.1wt%-5wt% of a coupling agent; and the balance sizing agent. The conductive filler is composed of nickel-plated glass fiber and nickel-plated graphite. Compared with the prior art, the composite conductive plastic provided by the invention adopt the conductive filler of specific composition, wherein the nickel-plated glass fiber is linear conductive filler, the nickel-plated graphite is flaky conductive filler, and coordination of the two with other components of specific content can achieve line-surface combination with good compatibility effect, thus forming a perfect conductive network, and on the basis of good mechanical performance, the product can have good conductivity and high electromagnetic shielding performance. The experimental result shows that the composite conductive plastic provided by the invention has surface resistance of 100m omega-200m omega and electromagnetic shielding effectiveness ranging from -60dB to -80dB.

Composite conductive plastic and preparation method thereof

Method of producing composite material based on nickel and graphite

The invention discloses a preparation method of iron-based alloy powder, and belongs to the technical field of powder metallurgy. The preparation method comprises the steps of: 1, preparing matrix powder and a plating solution; 2, sequentially putting the matrix powder into a plating solution for chemical plating; 3, and conducting diffusion operation on the plated powder, such that a diffusion speed of alloy elements in the powder is accelerated, and the diffusion uniformity is improved. According to the preparation method of the iron-based alloy powder, nickel-containing ferromolybdenum-based alloy powder is prepared through adopting a chemical plating method, and the prepared nickel-containing ferromolybdenum-based alloy powder has good performance.

Preparation method of iron-based alloy powder

The invention relates to a gun black electroplating senblacking agent. The gun black electroplating senblacking agent is a water solution made of carboxylic acid and carboxylate, and concentrations ofthe carboxylic acid and the carboxylate of the water solution are separately 40-55g/L and 85-120g/L. The invention further provides a gun black electroplating senblacking working solution which is formed by a mixture of the gun black electroplating senblacking agent and a tin-nickel alloy gun black electroplating technology addition agent in the prior art with a dosage ratio of 5-30mL:1L. The gunblack electroplating senblacking agent and the black working solution have the beneficial effects that after a senblacking agent is added into the existing tin-nickel alloy gun black electroplating technology addition agent, a gun black clad layer blackness L value can be reduced by 4-5 values, the clad layer appearance blackness is fuller, and the chromaticity is more elegant; and a traditionaltechnological condition and technological performance cannot be changed with the addition of the black agent, any adverse effect to the performance of a traditional electroplating solution and a cladlayer does not happen, the operation is simple, and the control is easy.

Gun black electroplating senblacking agent and senblacking working solution

The invention provides a graphite nickel plating method. The graphite nickel plating method comprises the steps of adding a graphite matrix into a nickel plating solution, and carrying out a reactionso as to obtain nickel plated graphite, wherein the nickel plating solution comprises the following components by content: 20 g/L to 35 g/L of nickel sulfate hexahydrate, 8 g/L to 30 g/L of lactic acid, 2 g/L to 18 g/L of triethanolamine, 20 g/L to 45 g/L of sodium citrate, 10 g/L to 35 g/L of ammonium chloride, 30 g/L to 45 g/L of sodium hypophosphite, 0.01 mg/L to 0.2 mg/L of L-arginine and 0.1mg/L to 10 mg/L of potassium ferrocyanide, pH is adjusted to be 8 to 9 through aqueous ammonia, and the temperature of the nickel plating solution is 30 DEG C to 45 DEG C. According to the graphite nickel plating method, complex technologies like surface degreasing, sensitization, metal palladium activation and peptization are eliminated, so that production efficiency is greatly improved; preciousmetal catalysis is not utilized, so that cost is reduced; and further, graphite powder is firstly subjected to copper plating and then is subjected to nickel plating, so that graphite powder has better electrical conductivity and tensile strength.

Graphite nickel plating method

The invention provides a deep pewter electromagnetic shielding material and a preparation method thereof. The electromagnetic shielding material is a flexible shielding material, the surface of the shielding material is in deep pewter, and the shielding material is composed of an electromagnetic shielding flexible substrate and deep pewter tin-nickel alloy on the surface layer. According to the deep pewter electromagnetic shielding material and the preparation method thereof, the tin-nickel alloy is free of sensitization to human bodies, and the corrosion resistance and tarnish resistance of the tin-nickel alloy are obviously better than those of monometallic nickel clad layers or monometallic tin clad layers; and meanwhile, the deep pewter electromagnetic shielding material has the good electromagnetic shielding effect and conductivity. In the aspect of color, the tin-nickel alloy of the electromagnetic shielding material is in the soft deep gun black different from silver gray of pure nickel, amaranth of pure copper and bright brass color of pure nickel, pure tin and pure copper. The material is excellent in shielding performance and good in corrosion resistance, has the good decoration, taking, protection, extinction, shading, heat absorbing, radiating and other properties, and can be widely used for the aspects of conductive adhesive tape, conductive woven cloth, conductive non-woven fabrics, shielding liners and the like.

Wang Zhengkun

Papers

Graphite nickel plating method

Deep pewter electromagnetic shielding material and preparation method thereof