Vacuum Induction Melting is a highly flexible process for manufacturing an extensive range of rare earth based metal and alloy systems.
With reference to phase diagrams, vapour pressure curves and Ellingham diagrams, LCM engineers have combined materials technology with manufacturing excellence to develop production techniques for a vast number of metals and alloys.
Microstructural control is achieved by careful selection of appropriate casting conditions. In some instances, material may be subjected to post-cast heat treatments in order to give the required grain size and phase distribution.
Individual melt sizes range from 5 to 300kg using any one of seven vacuum induction furnaces at LCM. Comprehensive production control provides excellent melt reproducibility and so individual batch sizes of any quantity are feasible, with typical production batches ranging from tens of kilograms up to two tonnes and above.
Co-Reduction
The manufacture of samarium cobalt alloys via the co-reduction of an oxide mix is a specialised process yielding very fine-grained high performance alloy powders. Co-reduction has now become the undisputed industry standard for SmCo5 production.
Since the acquisition of the co-reduction process from the inventors and patent holders, Elektro-Thermit, in 1996, LCM has worked extensively to improve process control and lower impurity levels. Furthermore, the development of co-reduced Sm2Co17 alloys offers a genuine alternative to cast and crushed alloys. Our range of co-reduced Sm2Co17 alloys is proven for reliable and efficient performance.
Different alloy compositions, tailored to give specific magnetic properties, are readily available. LCM technologists are able to advise on appropriate compositions for new applications. Variations on the process permit the incorporation of different rare earth oxides into the reactant mix; praseodymium and/or gadolinium being common additions to samarium cobalt based alloys.
Co-reduction is an extremely versatile technique, with production batches ranging in size from 200kg to 2000kg.
Powder Production
Several of LCM’s alloys and metals are supplied in the form of powders, manufactured either directly by co-reduction, or by the crushing and milling of cast materials. Gas or water atomised powders can also be offered depending on the requirements of the final product and application.
LCM powders are produced to closely controlled particle size distributions, with focus on consistent and reproducible materials in order to maximise reliability.
Materials that are susceptible to oxidation are processed under inert atmosphere in purpose built plant to yield low oxygen products. Other potential contaminants are minimised through the optimisation of specific powdering techniques for each product type. This expertise, coupled with the appropriate selection of precursor raw materials and pre-powder processing, results in products meeting the most demanding technical specifications.