The Low Superheat Casting (LSC) Process

Low superheat casting is similar to the better known SSM technique which can be applied primarily to produce billets with a low cost advantage.
In the LSC process, the alloy is rapidly solidified and cast with a low pouring temperature which is typically just above the liquidus temperature. Continue reading

Superplasticity of Aluminum Alloys: Part Two

Investigations into the superplasticity possibilities of aluminums can lead to many potential gains in finding lighter yet capable materials in terms of strength performance.
This article covers the high-temperature deformation behavior of 5083 at different annealing temperatures and yields some interesting conclusions. Continue reading

Superplasticity of Aluminum Alloys: Part One

It is known that superplasticity refers to the ability of a material to demonstrate under tensile tests very high uniform deformation more than several hundreds percents without visible necking. There are two basic requirements in order to achieve superplastic flow in a polycrystalline material. First, the material must have a very small and stable grain size less than 10 μm. Second, superplasticity is achieved only at relatively high temperatures above 0.5Tm (where Tm is the absolute melting temperature) because superplasticity is diffusion-controlled process. 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

Wrought Aluminum Alloys for General and Special Applications: Part One

The main groups of aluminum alloys which are the most often used in practice besides technically pure aluminum are AlMn, AlMg, AlMgMn, AlMgSi, AlZnMg, and AlZnMgCu alloys. These are wrought alloys which are shaped into products by rolling, extrusion, and forging. Each of the mentioned groups consists of numerous subgroups, depending on amounts of main and additional alloying elements, and they have tensile strength values varying in a wide range from 70 to 600 MPa.

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