Treatise on Applied Analytical Chemistry Volume 1; Methods and Standards for the Chemical Analysis of the Principal Industrial and Food Products (Paperback)

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. 1918 Excerpt: ...are as follows: Table XXII Composition of Brasses SPECIAL BRASSES By this name are indicated those alloys of copper and zinc which contain small quantities of one or more other elements (especially lead, tin, iron, manganese, aluminium) introduced for the purpose of imparting special properties. The most important are as follows. 1 Often contains 1-2% of lead. Sometimes contains also small quantities of tin, Lead Brasses. Lead brasses are very soft and therefore suitable for castings to be worked at the lathe. Their analysis comprises, besides determinations of copper and zinc, also that of lead and of the impurities usually occurring in ordinary brass (iron, tin, nickel, sulphur, phosphorus, arsenic, bismuth, etc.). The analytical methods are exactly those used for ordinary brass (q.v.). Lead brasses usually contain 1-3% of lead and such impurities as are found in common brass. Tin Brasses Tin brasses are used especially for making tubes, plates, valves, etc., for naval construction. They are analysed by the same methods as ordinary brass (q.v.). % Tin brasses contain on the average 6o-62% Cu, 37-5-39% Zn and 1-1-5% Sn. In this category fall Naval brass, Iloti brass and f.aveyssiire bronze. Manganese Brasses Manganese is introduced in small quantities into brass to increase the strength, elasticity and hardness. The constituents of these brasses are determined as with the complex brasses (see later). The two types in most common use have the compositions: (i) 5o-6o% Cu, 4o-41% Zn, traces of Mn, and (2) 58-59% Cu, 39-4o% Zn, 1-8-2-2% Mn. They are used in marine construction, especially for making propellers. The following table gives the compositions prescribed for manganese brasses by the American Society for the Testing of Materials and by the Technical B...