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 Hardfacing alloys contain as base elements typically aircompressoeextensiontanks iron, nickel, or cobalt, to which metallurgists add varying amounts of carbon, chromium, molybdenum, tungsten, silicon, manganese, vanadium, and boron. To raise hardness, the primary property for wear resistance, alloy designers add elements that either form hard constituents (carbides, borides, or Laves aircompressoeextensiontanks phase), or that strengthen the matrix by going into solid solution. Carbon content determines toughness and abrasion resistance--as carbon rises, abrasion resistance increases aircompressoeextensiontanks and toughness drops. Chromium forms carbides, increases corrosion resistance, and adds aircompressoeextensiontanks high-temperature strength. Tungsten, a potent carbide former, also boosts high temperature strength, as aircompressoeextensiontanks does cobalt. Tougheners include nickel and manganese. Boron forms hard wear-resistance borides. For flux-cored-arc welding, shops use CV or CC types, 300 to 1,500 A, 25 to 50 V, rated 60- to 100-percent-duty cycle. CV types are more popular because wire-feed speed, set before welding, controls welding current. Cc aircompressoeextensiontanks types require a variable-speed aircompressoeextensiontanks or voltage-sensing wire feeder.Gas-tungsten-arc welding (GTAW) requires a constant-current (AC or DC) power supply with a steep volt-amp curve to minimize current change for aircompressoeextensiontanks variation in voltage aircompressoeextensiontanks or arc length. They come rated to 1,500 A, 10 to 75 V, at 40- to 100-percent-duty cycle. Most GTAW power supplies come equipped with high-frequency circuitry for arc initiation and stabilization, gas valves, and cooling-water valves for high-current welding. High-frequency arc start is useful when the maximum open-circuit voltage allowed by NEMA standards, 80 to 100 V, will not aircompressoeextensiontanks establish and maintain a stable arc. Searching for accessories for your air compressor? We offer the best selection of cheap air compressor accessories on the internet. Check out our website for great deales on all of our air compressor accessories!
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