Practical alloying; a compendium of alloys and processes for brass founders, metal workers and engineers

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1920 Excerpt: ...the metal being cooled too much and allowing it to freeze to the sides of the ladle while casting. Phosphor bronze castings should not be dipped while still hot to blow the cores out. The phosphorus in the alloy renders it red-short. If you wish to see honeycombs all over the castings when they are machined, pour your phosphor bronze hot, into unslicked green sand molds. Many molders do this sort of thing and blame the bronze. The casting cleaner knows whom to blame. The best phosphor bronze does not necessarily contain the largest percentage of phosphorus. Phosphorus beyond the quantity required to produce homogeneous metal weakers the castings. Phosphorus is a powerful deoxidizer, but an excess may create a worse evil than oxide. The recognized limit for cast iron is 1 per cent, for bronze 3 per cent; the less phosphorus there is in the finished metal the greater the resiliency of the bronze. In steel of 1/30 of one per cent phosphorus would render the metal valueless for edged tools. Phosphorus introduced into ordinary bronze increases liquation and the tendency to segregation. Phosphorus makes copper hard and more liable to corrosion, but added to bronze--copper and tin alloy--less liable to corrosion. Phosphorus in bronze increases the grip of the patina or surface oxidation, so much sought after in ornamental bronzes. Phosphorus, in conjunction with zinc in a gun metal alloy, increases the co-efficient of friction; in conjunction with lead it reduces friction considerably. Kunzel was the first to deprecate the use of zinc in phosphor bronze. He patented an alloy which is now recognized as a splendid anti-friction metal for locomotive and other bearings liable to heat. Phosphorus has great affinity for iron and acts to chemically combine brass and iron...