Abstract: A method for forming a coating layer on a metal base material for a semiconductor reactor according to an aspect of the present invention comprises the steps of: immersing a metal base material for a semiconductor reactor in an aqueous alkaline electrolyte solution containing NaOH and NaAlO2; and connecting an electrode to the metal base material and supplying power to the electrode to form a coating layer on the metal base material through a plasma electrolytic oxidation (PEO) method.

Abstract: Disclosed is to a method for manufacturing a cobalt boride coating layer on the surface of iron-based metals by using a pack cementation process. In particular, the present invention relates to a method for manufacturing a cobalt boride coating layer by forming a composite coating layer on the surface of steels which is composed of an outmost layer having a composition of cobalt boride (Co2B) and an inner layer having a composition of iron-cobalt boride ((Fe,Co)2B). Since the cobalt boride coating layer is a compact coating layer having little defects such as pores, it can improve physical properties such as corrosion resistance, wear resistance and oxidation resistance of steels.

Abstract: The present invention relates to a composite layer including a metal and inorganic powders, and a method for manufacturing the same. The method for manufacturing a composite layer including a metal and inorganic powders includes step of preparing an electrolyte which includes nickel sulfamate [Ni(NH2SO4)] at 50.0 g/l˜300.0 g/l, boric acid at 10.0 g/l˜20.0 g/l, nickel chloride (NiCl2) at 1.0 g/l˜10.0 g/l, coumarin (C9H6O2) at 0.02 g/l˜0.5 g/l, sodium dodecyl sulfate [CH3—(CH2)11—OSONa] at 4.0 g/l˜60.0 g/l, sulfuric acid at 0.0 ml/l˜150.0 ml/l, one or more inorganic powders selected from the group of alumina (Al2O3) and silicon carbide (SiC) at 20.0 g/l˜70.0 g/l, and the remainder being distilled water. A basic metal to be coated with the composite metal is dipped into the electrolyte, and power is applied to the basic metal to electroplate the basic metal with the electrolyte to form a composite layer on the basic metal.

Abstract: The present invention relates to a composite layer including a metal and inorganic powders, and a method for manufacturing the same. The method for manufacturing a composite layer including a metal and inorganic powders includes steps of preparing an electrolyte including nickel sulfamate [Ni(NH2SO4)] at 50.0 g/l˜300.0 g/l, boric acid at 10.0 g/l˜20.0 g/l, nickel chloride (NiCl2) at 1.0 g/l˜10.0 g/l, coumarin (C9H6O2) at 0.02 g/l˜0.5 g/l, sodium dodecyl sulfate [CH3—(CH2)11—OSONa] at 4.0 g/l˜60.0 g/l, sulfuric acid at 0.0 ml/l˜150.0 ml/l, one or more inorganic powders selected from the group of alumina (Al2O3) and silicon carbide (SiC) at 20.0 g/l˜70.0 g/l, and the remainder being distilled water; dipping a basic metal into the electrolyte; supplying a powder to the basic metal and electroplating the basic material; and forming the composite layer on the basic metal.

Abstract: The embodiments of the invention relate to a MoSi2-SiC nanocomposite coating layer formed on surfaces of refractory metals such as Mo, Nb, Ta, W and their alloys. The MoSi2-SiC nanocomposite coating layer is manufactured by forming a molybdenum carbide (MoC and MoC2) coating layers on the surfaces of the substrates at high temperature, and the subsequent vapor-deposition of Si. The MoSi2-SiC nanocomposite coating layer has a microstructure in which SiC particles are mostly located on the equiaxed MoSi2 grain boundary. The MoSi2-SiC nanocomposite coating layer can have a close thermal expansion coefficient to that of the substrate by controlling a volume fraction of SiC particles exisiting in the nanocomposite coating.

Abstract: A NbSi2-base nanocomposite coating formed on the surface of niobium or niobium-base alloys is disclosed. The nanocomposite coating layer is manufactured by forming a niobium carbide layers or a niobium nitride layers by depositing of carbon or nitrogen on the surface, and then depositing silicon. The nanocomposite coating layer has a microstructure that SiC or Si3N4 particles are mostly precipitated on an equiaxed NbSi2 grain boundary. The thermal expansion coefficients of NbSi2-base nanocomposite coating layers become close to that of the substrates by adjusting the volume fraction of SiC or Si3N4 particles in the nanocomposite coating layers. Accordingly, the generation of cracks caused by thermal stress due to the mismatch in thermal expansion coefficient between the NbSi2-base nanocomposite coatings and the substrates can be suppressed, thereby improving the high-temperature oxidation resistance in the repeated thermal cycling use of the NbSi2-base nanocomposite coated substrates.

Abstract: Corrosion resistant multi-layered clad plates or sheets with high bonding strength is disclosed. According to the present invention, clad metals with high corrosion resistance such as Ti, Nb, V, or Zr and their alloys can be bonded with a cheap substrate such as Fe, Cu, or Ni and their alloys by the resistance seam welding. Using the insert metal causing the eutectic reaction, the clad metal can be strongly bonded with the substrate. Especially, corrosion resistant clad plates with excellent bonding strength can be fabricated by controlling the thickness and the microstructures of the eutectic reaction layer at the interface between the clad metal and the substrate or between the clad metal and the insert metal.