Metcalf at General Motors Research from April 1955 to Oct 1955
My first task was to clean up the alloy and metals storage bins while the construction people completed installing the melting equipment. It was my first chance to touch the elements that I studied in high school and college. Picking up a piece of tungsten and a piece of beryllium was my first shock. They looked alike but one felt ten times heavier than the other did. This experience sent me to my old chemical handbook where I copied down all the densities of the metals in the storage bins. I also made a chart of the melting and boiling points of these metals.
The work included operation of several types of electric fed pots for melting metals. The melt shop foreman gave me my first mixture to melt down. The first mix was simple cast iron that consisted of iron, carbon, and silicon. This mix was the foundation of the Iron Age that man probably found where a wood fire burned on top of the earth where sand and iron ore was present.
The first melt taught me the awesome power that was released when carbon was added to oxidized liquid iron. More than half of the 100-pound melt in the brand new Ajax electric induction crucible boiled over the top when I attempted to add four percent carbon to start the process of melting cast iron. This failure was allowed by the melt shop foreman to teach a headlong hillbilly a lesson.
A bug bit me that day! Watching solid metal melt in a pot where no visible source of heat was apparent released the Don Quixote in me. I fought the windmill called electricity the rest of my days without fully understanding just how it worked.
Dr. Weber asked me to come to his office after the mess around the melting furnace was cleaned up. He told me that I had been baptized and now could help him with a very important task he was working on at that time. He gave me copies of diagrams that showed how melting points of materials changed when mixed together. He gave me tables on the free energy of formations between metals and their oxides. He told me to study the iron carbon diagram and the free energy between carbon and carbon dioxide. I learned my foundation in metallurgy that night. He taught me another very important lesson in metallurgy. Molten metal attracts metal, slag attracts slag and gases attract gases. He was sure we could develop a system of slag and inert gases to produce the new alloys without using vacuum as the protective atmosphere.
Ford was already producing jet engines with Pratt and Whitney and General Electric leading the way. He told me that GM did not want to miss out of a coming mode of mass transportation using jet engines. He was working on a new high temperature, high strength alloy for the jet blade called GMR 235. He was sure that he could develop a version of Waspaloy that would not require melting in vacuum. GM had set up a large air melting casting facility at another location and was betting the store on their new engine for the Electra aircraft.
Dr. Weber assigned me to another technician to make the melts and the castings for his test blades for GMR 235. A strange thing happened; he let me decide how to mix and melt the alloys to match his planned recipe. Each night I studied the documents he had given me until it was time to fall asleep. The first melts were covered with deep slag when I added the aluminum and titanium. I went to Dr. Weber's office with a plan to put a lid on the furnace and use a reducing gas. My comment was "if oxygen ain't there it can't oxidize. My suggestion to use Freon gas was accepted. The final step was to kill the final slag with calcium metal. At high temperatures the Freon converted to phosgene and it is a wonder I did not poison myself.
The metal was melted in a 17-pound furnace that was powered by a 25,000-cycle Ajax spark gap converter. The electrical connections were through copper rods sitting in a mercury pots. After the melt was ready I would pick up the furnace and carry it to a pouring box mounted over a water tank. The pouring box was ceramic with several hundred small holes in the bottom. The metal would run out the holes into the water to form shot that looked like cornflakes. I could produce about ten melts in an eight-hour shift with others collecting the shot from the water tank. In eleven working days I completed all the eleven mixes that had eight melts each.
Dr. Weber heard my wife was in the hospital having a baby. He called me into his office and said, "A man should be with his wife during two moments, one at conception and the other at birth." He sent me to the mountains to see my new daughter, Debra, in April 1955.
The next step in the production of cast blades depended upon my partner, who was making the molds that formed the shape of the blade. The use of plaster of Paris to form a reverse mold had been used for several hundred years before the dentist profession used it to make an impression of gums and teeth. They filled the impression with wax to make a mold then poured wet ceramic around it. After the ceramic was dry heat was applied to melt the wax and cure the ceramic. I would make the melt in a 6-pound furnace, and set it a fixture that could be turned upside down.
My partner carried an upside down hot mold and placed it on the furnace. I would clamp the two together and using a handle would roll the assembly over. This allowed to liquid metal to fill and the result when cooled was a jet blade. After a little more machine work the blade was ready to spin in the jet engine.
My body was on display when President Eisenhower came to view the laboratory inaugural. I was melting a sparkling cast iron melt when he walked around the glass enclosed balcony above the foundry floor. A sign my buddy had hung on the crane block above my head was DO NOT FEED THE MONKEYS.