Archive for December, 2007
Monday, December 31st, 2007
Brazing is a group of welding processes which produce coalescence of materials by heating them to a suitable temperature and by using a filler metal having a liquidus above 450oC and below the solidus of the base metals.Filler materials for brazing are covered by an AWS specification. They are classified ...
Posted in Welding Brazing and Soldering | Comments Off
Monday, December 31st, 2007
The strength, hardness, and modulus of elasticity of magnesium-base materials decrease with increasing temperature. Also, the elongation increases with rising temperature up to just below the melting point where it drops to nearly zero. Some magnesium alloys have been developed recently for use at moderately elevated temperatures. These compositions make ...
Posted in Magnesium | Comments Off
Monday, December 31st, 2007
Corrosion involves the interaction (reaction) between a metal or alloy and its environment. It is affected by the properties of both the metal or alloy and the environment. In this discussion, only the environmental variables will be addressed, the more important of which include:
* pH (acidity)
* Oxidizing power (potential)
* Temperature ...
Posted in Metal | Comments Off
Monday, December 31st, 2007
Aluminum alloys have numerous technical advantages that made them one of the dominant structural material families of the 20th century. Aluminum has low density (2.71 g/cm3) compared with competitive metallic alloy systems. It also has good inherent corrosion resistance because of the continuous, protective oxide film that forms very quickly ...
Posted in Cobalt | Comments Off
Monday, December 31st, 2007
The copper alloys may be endowed with a wide range of properties by varying their composition and the mechanical and heat treatment to which they are subjected. For this reason they probably rank next to steel in importance to the engineer.
The important alloys of copper and zinc from an industrial ...
Posted in Cobalt | Comments Off
Monday, December 31st, 2007
This article provides a general overview of cobalt-base alloys as wear-resistant, corrosion-resistant, and/or heat-resistant materials. Particular emphasis is placed on cobalt-base alloys for wear resistance, because this is the single largest application area of cobalt-base alloys.
Cobalt is useful in applications that utilize its magnetic properties, corrosion resistance, wear resistance, and/or ...
Posted in Cobalt | Comments Off
Friday, December 28th, 2007
Stainless steels are commonly divided into five groups: martensitic stainless steels, ferritic stainless steels, austenitic stainless steels, duplex (ferritic-austenitic) stainless steels, and precipitation-hardening stainless steels. Stainless steels are available in the form of plate, sheet, strip, foil, bar, wire, semi-finished products, pipes, tubes, and tubing.
Stainless steels are iron-based alloys containing ...
Posted in Stainless Steel | Comments Off
Friday, December 28th, 2007
The low-alloy high-strength steels represent the bulk of the remaining steels in the AISI designation system. These steels are welded with E-80XX, E-90XX, and E-100XX class of covered welding electrodes. It is also for these types of steels that the suffix to the electrode classification number is used.This article gives ...
Posted in Steels, Welding | Comments Off
Friday, December 28th, 2007
Alloy steels may be divided into four classes:
(1) Structural steels, which are subjected to stresses in machine parts.
(2) Tool and die steels.
(3) Magnetic alloys.
(4) Stainless and heat-resisting steels.
Structural steels
The structural steels can be grouped conveniently on the basis of tensile strength. However, the dividing lines between the classes are ill ...
Posted in Alloy Steel | Comments Off
Friday, December 28th, 2007
Tool steels are groups into six types: high speed, hot work, cold work, shock resisting, special purpose and water hardening. High-speed steels are very efficient with heavy cuts and high speeds they are incapable, at slow speeds and lighter cuts, of holding the keen edge necessary for obtaining a very ...
Posted in Metal News | Comments Off