| 摘要 |
<p>A coating paste for welding electrodes comprises slag-forming materials, water glass, moulding lubricants and 0.5-3% by weight of polyoxyethylene which has a molecular weight of at least 103. The paste may include such materials as feldspar, bentonite, kaolin, talc, rutile, manganese oxide, ferric oxide, calcium carbonate, asbestos and calcium fluoride as slag formers, carbon hydrates, titanates, powdered metals, e.g. Fe, FeSi, SiMn, FeMn, and alginates. The polyoxyethylene which acts as an anti-crack agent consists of a straight-chain including at least twenty oxyethylene groups, e.g. polywax or carbowax. The powdered materials finer than 0.6 mm. mesh are dry mixed, water glass is added followed by wet mixing. The paste is used for coating metal cores such as stainless steel, nickel, bronze, mild steel, or "Monel" (Registered Trade Mark). The coated cores are then dried and fired.</p> |
