Originally shared September 14, 2023

The article we will be sharing this week is a little different in that aspects of what it suggests have been partially adopted since its publication in 1988, but they have not been adopted fully. Written by TAT’s President Harb Nayar during his time at BOC, the article covers the advantages of transitioning from conventional PM sintering to his “zoning” concept. Almost universally common now, zoning in PM furnaces was only just beginning to take place at a few early adopter plants when this paper was published.

It has since dramatically improved the performance and productivity of sintering operations across the industry by replacing conventional Endo gas atmosphere sintering (one static gas, no zones) with multi-zone, multi-gas atmosphere combinations. Typical atmosphere zoning, as well improved zoning methods yet to be fully adopted, would not be possible if not for Harb Nayar’s earlier invention of N2-H2 sintering atmospheres developed in the 1970s. He has has a huge impact on the industry over the course of his long career!

However, Harb believes that the industry has cheated itself by not following through with the ideas and recommendations in this paper. While most do follow the zoned system concept, very few kept going and evolved to the super zoned system (increasing number of zones) or the computerized super zoned system (automated zone adjustments). Had companies continued to develop their zoning systems, individual companies, and the PM industry in general,would be much more efficient and profitable through a dramatic increase in throughout today.

But there is always still time to evolve, so please keep that in mind when reading the paper below! You will read about the disadvantages of conventional sintering, the advantages of zoned sintering, and why there are huge benefits to be gained from adopting the improved systems of zoning outlined in the paper. It is titled Productivity and Quality Improvements Via Design and Process Changes in the Conventional Sintering. (MPIF-1988-0185)

A full PDF copy will be given by request if you contact This email address is being protected from spambots. You need JavaScript enabled to view it.

The importance of zoning and how to get the most out of it is a major focus of TAT Technologies’ training classes. If you’d like a hands-on demonstration of the concepts covered in today’s shared article, our classes are a great place to start! The next date they are scheduled to begin is October 24. Please use this link to visit the training section of our website and review the options on the sidebar. Please contact me with any questions and registration.

If you have any questions or comments, please contact me and I’ll be happy to answer.