Semi-Solid Rheocasting of Alumina Alloys: Part One

Aluminum is well established at the front of the pack with regards to providing the technological answer to the increasing challenges of light weighting whilst maintaining integrity of the material for the desired applications.
Semi solid rheocasting is a development within the casting sector which enables improved quality in die casting without increasing cost. Continue reading

Intercritical Annealing of Ductile Iron: Part One

Heat treatment can be performed on ductile iron to increase strength, wear resistance, ductility, toughness, and/or improve machinability by controlling the matrix microstructure. In F, an intercritical heat treatment starts with partial austenitization in the intercritical region where ferrite and austenite are present. The amount of austenite depends on the chemistry of the alloy and the temperature. Continue reading

High Chromium Cast Iron: Part Two

High chromium cast irons (HCCI’s) exhibit very good mechanical properties and offer benefits for a range of manufacturing applications.
One of the main flexibilities exhibited is the possibility of HCCI’s to have different matrix structures in different treatment states whether it be austenite in casting state, pearlite in annealing state, martensite in quenching state, and tempered martensite in tempering state.
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Microstructures in Austenitic Stainless Steels

Austenitic steels may undergo microstructural changes during short- or long-term exposure to high temperature. In the case of longer ageing times, other precipitates such as intermetallic phases are formed, which are usually accompanied by dissolution of carbides.
The intermetallic precipitations are of great interest not only because they exert influence on the mechanical properties but also because of their strong effect on the corrosive properties.

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Ultra Low Carbon Bainitic Steels: Part Two

Although one of the most hotly debated microstructure topics, control of bainitic transformation can lead to a range of diversified gains over the mechanical properties of the finished product.
Specific studies of the relationship between cooling rate and finished cooling temperature show interesting findings related to the distribution of granular bainite, martensite-austenite constituent, bainitic ferrite, and polygonal ferrite.

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Fatigue, Fracture and Microstructure Relationships of an Aluminum Automobile Component

Aluminum alloys are progressively used in the automobile industry due to several advantages such as low specific weight, good formability, good corrosion resistance and a nice surface appearance. The standard production forming processes such as extrusion and forging, can give rise to large variations in the tensile, fatigue and fracture properties. In AlMgSi alloys (6061, 6062, 6060 and 6082), yield stress have been shown to have only a weak dependence on grain size. However, a large part of the variations in other properties can be traced back to differences in grain size.
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