摘要:
An inexpensive rotary grinding tool with reduced noise level of the grinding is provided. The rotary grinding tool comprises a metal disk having a grinding surface on at least a part of its surface and a holder for supporting the metal disk. The grinding surface has hard grains having a Mohs hardness in excess of 9 brazed thereon at a surface density of at least 20 grains/cm2. The holder has at its center a securing means for securing the holder on rotary shaft of a rotary drive unit. The holder and the metal disk are joined together to constitute the rotary grinding tool.
摘要翻译:提供了具有降低的磨削噪音水平的廉价的旋转磨削工具。 旋转研磨工具包括在其表面的至少一部分上具有研磨表面的金属盘和用于支撑金属盘的保持器。 磨削表面具有以至少20个/ cm 2的表面密度在其上钎焊的莫氏硬度超过9的硬质粒。 保持器在其中心具有用于将保持器固定在旋转驱动单元的旋转轴上的固定装置。 保持器和金属盘连接在一起以构成旋转研磨工具。
摘要:
A highly durable separator for solid polymer fuel cells that can be produced at low cost and that is characterized by the separator having a flat portion in the peripheral portion and channels in the central portion composed of protruded portions and recessed portions which provide flow paths for gases on the front surface and the back surface, and the shape of each channel end portion being tilted.
摘要:
A corrosion detecting probe is to be used in combination with a known electrochemical measuring apparatus for inspecting corrosion state of a steel material buried in a concrete structure. The probe comprises a container made of an electrically insulating material and having an open end adapted to be placed in close contact with a surface of the concrete structure, a cover closing the open end and made of a porous and liquid permeable material, an electrolyte liquid solution filling the container so that the cover is sufficiently impregnated with the solution, and an electrode assembly mounted within the container so as to be immersed at least partially in the electrolyte solution. The electrode assembly includes an elongated reference electrode having a free end portion at least partially immersed in the electrolyte solution, a counter electrode having an electrode plate of a symmetrical configuration with respect to the free end portion of the reference electrode and distanced therefrom, and a current flow line control electrode having an electrode plate of a symmetrical configuration with respect to the free end portion of the reference electrode and disposed in a same plane as the electrode plate of the counter electrode at a distance therefrom.
摘要:
A method of detecting the rate of corrosion of an existing steel structure installed in a corrosive environment is disclosed. The method includes treating a measurement surface of the member so that an AC impedance of the measurement surface, when electrochemically measured at a predetermined high frequency range of potential variation applied to the measured surface, takes a first valve within a predetermined range; and second value of the impedance is then electrochemically measured at a low frequency range of potential variation applied thereto. The difference between the first and second values is calculated to detect the corrosion-reaction resistance of the surface and the rate of corrosion is determined on the basis of the detected corrosion-reaction resistance and according to a pre-calculated relation between the rate of corrosion and the corrosion-reaction resistance.
摘要:
A highly durable repair-coating method is provided, which permits the simple, fast, efficient and effective removal of thick rust and fixed rust generated on a steel structure having a large area such as a bridge and an intermediate iron product, under storage, which can ensure high working properties and high safety while reducing the processing cost, and which can likewise ensure high quality repairing and the subsequent improved duration of the repaired and coated articles.The method is for highly durable repair-coating of a coated or coating-free steel structure which comprises the steps of conditioning the ground of the coated or coating-free steel structure such that the rate of exposed surface area of the ground is not less than 60%; and then applying an aqueous solution of sodium carbonate having a concentration of not less than 5 g/L and not more than 500 g/L, as a prior processing solution; and further optionally applying a highly corrosion-resistant zinc powder-containing composition which comprises 100 parts by mass of a binder resin (the solid content by mass); 200 to 800 parts by mass of zinc powder; 1 to 95 parts by mass of a corrosive ion-fixing agent; and 200 to 1,000 parts by mass of a solvent.
摘要:
A predicted corrosion amount of a painted or unpainted atmospheric corrosion resistant steel is calculated by using extrinsic corrosion information including weather observation data, an amount of airborne salt, and an amount of sulfur oxide in a planned location for use where the atmospheric corrosion resistant steel is to be used, and intrinsic corrosion information on components of the atmospheric corrosion resistant steel. The weather observation data on this occasion preferably includes the annual wetness time, annual mean wind speed, and annual mean temperature. Moreover, it is preferable to calculate a corrosivity index, estimate a first-year corrosion amount of the atmospheric corrosion resistant steel and a rust stabilization index from the corrosivity index, and calculate a corrosion amount accumulated over time.
摘要:
The present invention provides a metal foil excellent in electrical contact stability, and low in cost, by eliminating plating processes. Specifically, the present invention is a metal foil excellent in electrical contact stability characterized by having a surface roughness wherein the ratio Ra/Sm between the arithmetic average of roughness Ra and the average interval Sm of concavities and convexities is 0.001 or more, which average values are obtained by measuring the roughness in the direction in which the average interval Sm of the concavities and convexities on the surface is smallest. It is preferable that the material of the metal foil is stainless steel or phosphor bronze.
摘要:
A sensor for electrochemical measurement is disclosed which includes a chamber made of an electrically insulative material and having an open end portion, a super absorbent polymer material filled in the chamber and absorbing at a selected rate a liquid electrolyte, an electrode disposed in the chamber, and a screen which covers the open end portion of the chamber and which prevents the super absorbent polymer material from dropping out from the chamber but permits the liquid electrolyte to transmit through the screen. A method is also disclosed which uses the sensor to measure the degree of degradation of a coating film on metal or the corrosion protective properties of a rust film created on the surface of steel.