EARLY TECHNICAL ARTICLES

Heat Treating Magazine Series Articles

During the period from July 1981 to June 1984, I was invited by the editors of “Heat Treating” Magazine to
author a series of eighteen articles which represented a comprehensive coverage of many of the aspects of
heat treating aluminum alloys. Subjects covered were temper nomenclature, solution heat treating,
quenching, racking, and aging. Although since that time, many of these articles have been expanded on
myself and others, they still represent a reasonable coverage of many of the basics principles of aluminum
heat treating and have been used by myself and others to provide fundamental training, particularly to those
just being introduced to the subject. To insure that this material remains a source for those interested, we
have decided to post this series on my website on the internet, and break it up according to subject matter.
These groupings are as follows:

Series 1 -    Introduction and Temper Designations; A series of three articles.


                     (click HERE to obtain .pdf copy of original articles)

                    1)  “Introduction To Heat Treating Aluminum Alloys", By Tom Croucher; HEAT TREATING,
                          November 1981. Volume XIII No. 11, pages 16, 19.
                    2)  "Heat Treated Aluminum Alloys: Temper Nomenclature, Part 1", By Tom Croucher; HEAT
                          TREATING, July 1981. Volume XIII, No. 7, pages 19-20.
                    3)  "Heat Treated Aluminum Alloys: Temper Nomenclature, Part 2", By Tom Croucher; HEAT
                          TREATING, September 1981. Volume XIII, No. 9, pages 68-69.

Series 2 -     Solution Heat Treating; A series of two articles.


                     (click HERE to obtain .pdf copy of original articles)

                    1)  "Solution Heat Treating Of Aluminum: Part 1", By Tom Croucher; HEAT TREATING, January
                          1982. Volume XIV, No. 1, pages 20-21.
                    2)  "Solution Heat Treating Of Aluminum Alloys: Part 2", By Tom Croucher; HEAT TREATING,
                          March, 1982. Volume XIV, No. 3, pages 18-19.

Series 3 -       Quenching of Aluminum Alloys; A series of five articles.

                    
 (click HERE to obtain .pdf copy of original articles)

                    1)  "Quenching Of Aluminum Alloys: What This Key Step Accomplishes," By Tom Croucher;
                          HEAT TREATING, May 1982. Volume XIV, No.5, pages 20-21.
                    2)  "Quenching Of Aluminum Alloys: How To Determine The Optimum Quench Rate", By Tom
                          Croucher; HEAT TREATING, July 1982. Volume XIV, No. 7, pages 16-17.
                    3)  "Water Quenching For Aluminum Alloys", By Tom Croucher; HEAT TREATING, September
                          1982. Volume XV, No.9, pages 18-19.
                    4)  "Polymer Quenchants: Their Advantages For Aluminum Alloys". By Tom Croucher; HEAT
                          TREATING, November 1982. Volume XIV, No.11, pages 18-19
                    5)  "A Systems Approach To Quenching Aluminum Aids Dimensional Stability", By Tom Croucher;
                          HEAT TREATING, January 1983. Volume XV, No. 1, pages 16-17.

Series 4 -      Racking of Parts; A series of three articles.


                     (click HERE to obtain .pdf copy of original articles)

                    1)  "Proper Racking - the Key to Distortion Control for Aluminum Alloys", by Tom Croucher and
                          Denny Butler; HEAT TREATING, March 1983. Volume XV, No. 3, pages 19-20.
                    2)  "Racking For the Quench: Critical Factors for Controlling Distortion", by Tom Croucher and
                          Denny Butler; HEAT TREATING, May 1983. Volume XV, No. 5, pages 16-17.
                    3)  "Quench Racking, Additional Factors to Consider", by Tom Croucher and Denny Butler; HEAT
                          TREATING, July, 1983. Volume XV, No. 7, pages 7-8.

Series 5 -      Aging of Aluminum Alloys; A series of five articles.

                     (click HERE to obtain .pdf copy of original articles)


                    1)  "Purposes and Methods of Aging Aluminum Alloys", by Tom Croucher; HEAT TREATING,
                          September 1983. Volume XV, No. 9, pages 18-19.
                    2)  "Understanding the Use of Artificial Aging for Aluminum Alloys", by Tom Croucher; HEAT
                          TREATING, December 1983. Volume XV, No. 12, pages 12-13.
                    3)  "Aging Reactions, How They Occur, What They Accomplish", by Tom Croucher; HEAT
                         TREATING, February 1984. Volume XVI, No. 2, pages 12-13.
                    4)  "Miscellaneous Aging Factors: Understanding the Need for Multi-step Aging", by Tom Croucher;
                          HEAT TREATING, April 1984. Volume XVI, No. 4, pages 18-19.
                    5)  "Precipitate Regression: Effects of Quench/Age Delay and Rate of Heating", By Tom Croucher.
                          HEAT TREATING, JUNE 1984. Volume XVI, No. 6, Pages 23-23.


Articles on Distortion Control: A series of three articles:
In addition, in the early days of my career in the 1970's, we conducted extensive research into the
benefits of glycol quenchants in controlling distortion of high strength aluminum parts. At the time,
much of this work was sponsored by Tenaxol and by the Northrop Corporation. As a result of this
research, we inaugurated the first production quenching of thicker parts other than sheet metal using
glycol quenching. In the early 1970's, we were the first to glycol quench both hand and die forgings,
and precision aluminum castings. We also inaugurated the practice of quenching net and near net
machined parts in order to reduce internal residual stresses. This practice has since become a
standard practice of many companies. Most of this production work was being done long before
there were any specification requirements or guidance for these procedures.

Series 6 -      Distortion Control; A series of four articles represents this effort:

                     (click HERE to obtain .pdf copy of original articles)


                    1)  "Distortion Control of Aluminum Products Using Synthetic Quenchants" by Thomas R. Croucher
                          and M. Daniel Schuler. Presented at the 1970 Western Conference of The American Society for
                          Metals, March 1970, Los Angeles. Published in METALS ENGINEERING, QUARTERLY,
                           August 1970.
                    2)  "Applying Synthetic Quenchants to High Strength Alloy Heat Treatment" by Thomas R. Croucher.
                         Presented October 1970 at the ASM National Metal Congress, Cleveland, Ohio. Published in
                         METALS ENGINEERING QUARTERLY, May 1971.
                    3)  "Synthetic Quenchants Eliminate Distortion" by Thomas R. Croucher, Published in METAL
                         PROGRESS, November 1973. 
                    4)  "Polymer Quenching of Top Quality High Strength Aluminum Castings" by Tom Croucher;  HEAT TREATING 
                           October 1982.    

Articles on Residual Stress Control; A series of four articles.
Upon successful application of the glycol quenchants to thicker products, in the 1980's, our efforts
turned to determining if the use of glycol quenching methods could be used in a systems approach to
controlling residual stresses which constantly lead to machining distortion. This also lead to
investigations as to the benefits of uphill quenching techniques, and particularly the integration of
glycol quenching with uphill techniques to achieve optimum stability. This led to the publication of a
series of four articles:
 
Series 7 -    Residual Stress Control; A series of four articles represents this effort:

                     (click HERE to obtain .pdf copy of original articles)


                    1)  "How to Achieve Dimensional Stability In Aluminum Alloys" by Tom Croucher and Denny Butler.
                    HEAT TREATING, Vol XII, No. 9. September 1980.
                    2)  "Quenching: Major Stress Source in Heat Treated Aluminum Alloys" by Tom Croucher and Denny
                    Butler. HEAT TREATING, Vol XII, No. 10. October 1980.
                    3)  "A Systems Approach To Quenching Aluminum Aids Dimensional Stability", By Tom Croucher;
                    HEAT TREATING, January 1983. Volume XV, No. 1, pages 16-17.
                    4)  “Uphill Quenching of Aluminum; Rebirth of a Little Known Process” by Tom Croucher; HEAT
                    TREATING; October 1983