What happened to the heavy metal market in 2017?, page-2

Meanwhile, back at the ranch, Dy deletion continues apace right done thru the NdFeB range, not so much as a supply issue anymore but rather driven by the constant competition to produce the most cost effective product, and as you can see they've found a while bunch of ways to do it:

"In order to reduce the cost and support the sustainable growth of the Nd-Fe-B magnet market, many producers started to develop HRE-free high intrinsic coercivity Nd-Fe-B magnets, and have made significant progress in recent years. As shown in Figure 1, with the exception of N46SH, nearly all grades of Nd-Fe-B magnets with intrinsic coercivity less than 20 kOe can be made without heavy rare earths, which can satisfy the majority of requirements for industrial applications. The need for heavy rare earth has also been significantly reduced for Nd-Fe-B magnets with intrinsic coercivity of 25 to 30 kOe."



"The magnetic properties of Nd-Fe-B are determined by chemical composition, process parameters, and final microstructure. The following is a list of important factors to consider in the development of HRE-free and HRE-lean Nd-Fe-B sintered magnets:

• Low oxygen and other impurities
• Smaller and more uniform grain size
• Finer and more uniform microstructure of precursor strip cast alloys
• Smaller powder particle size after jet milling
• Better powder particle size distribution
• Better magnetic alignment
• Better sintering equipment and temperature uniformity
• More uniform quenching
• More uniform gain boundary phase
• Grain boundary engineering

There are of course many other process details involved in the successful development of HRE-free magnets. Some of the factors above are actually interrelated. Lowering the impurity level and reducing the material oxidation would help increase the residual induction, Br, and maximum energy product, (BH)max, while smaller grain size can help increase the intrinsic coercivity, Hci, without the need for the extra addition of heavy rare earths such as Dy."

http://magneticsconference.com/recent-developments-and-trends-in-nd-fe-b-magnets/

Bye bye Dy, the great HRE spin can be laid to rest.