Saturday, November 28, 2020

 New Lessons Regarding Lubrication and Binding of Alloy Sub-Micron Powders

    It has been awhile since I have had the urge to write an article on metallurgy. Perhaps it was the pandemic or even though we are entering a space age era, a lack of going forward during this period of time. Actually advanced manufacturing has overwhelmed the technical realm and I am not the biggest fan of advanced manufacturing, not that I am not a believer of advancement, but I am resistant of letting computers do it for us.

    For instance, there is much publicity of advancements that are occurring to lighten materials and to introduce new lighter materials. This occurs through mostly two dimensional design, but more ideally through complex three dimensional design, with precision  possible only using a computer.

    Yes there are advantages to this, as well as disadvantages. One advantage is that it makes possible design of new alloys without conducting as much lengthy and costly experimentation. However, all of this is dependent on the experience of the individual that is operating the computer. However, if done correctly and with execution of essential experimental background work, then strength and toughness may be increased. In magnetic materials core loss and design of magnetic components can be maximized. Yes, even corrosion, the most expensive problem in modern society, can be reduced.. So yes, there are benefits, but dangers as well.

    The reason for all of this to happen is because in most advanced manufacturing processes where laser or electron beam technology is employed for fusing or melting the powder, a fine layer of sub-micron powder is distributed throughout the surface  of the area to be built.Unfortunately, fine sub-micron powders do not flow well. Therefore a binder is required to increase their size and agglomerate them into larger composite spheres to satisfy this requirement. This brings me back 40 years ago when I was in charge of a research section at Hoeganaes Corp. One of my projects was to develop a lubricant that would improve the flow of  stainless steel powders.These powders were larger, but not quite speroidal in shape. We at that time worked with a Lanza powder that permited us to reduce the quantity of lubricant admixed to 0.5 %. 

        Now MagnaTech is currently working to develop a new refractory metal powder that is manufactured as sub-micron powder and the additives are also sub-micron in size. Therefore the requirement is to find an additive that not only agglomerates these powders but also  provides sufficient lubrication to permit flow within a restricted die cavity. Therefore, MagnaTech also finds itself into development of lubricants with good binding properties.Right now there are a few other small companies that are starting to enter this field too If these new advanced manufacturing processes are to succeed,  a  free-flowing powder must be developed that will bind the sub-micron particles into a powder sufficiently large and ideally spherical to provide the uniform layers that will be fused or melted incrementally that will eventually build to form a solid shape of required dimensions MagnaTech sees a niche for itself in development of new binder /lubricants to resolve one of the problems currently causing problems in some advanced manufacturing processes.