Ceramic engine development (1990s ceramics hype)

Promised automobile engines and turbine engines, delivered onion-slicing knives.

So now 30 years later, what do we make out of fine ceramics? They were going to make automobile engines, they were going to make turbine engines for aircraft. What do we make? I've got some knives at home — excellent at slicing onions, because of the sharpness, they don't crush the cells and release all those things that make you cry. They actually cut through the cells and don't release as much of the juice. In the mid-80s I used to give this talk and say, we're not going to have structural ceramics because they don't have fracture toughness. Look at that piece of silicon, the little flat piece with the chips on it. Look at my knives in my kitchen — they don't have tips on them, they've got chips on them. They retain their sharpness as long as they don't chip off and turn into something blunt.

Mid-1980s/early-1990s ceramic-engine research push. Ceramists "knew nothing" about fracture toughness; spent hundreds of millions trying to build all-ceramic internal combustion engines while metals research starved. Brittleness, chloride corrosion, sub-paper-thickness critical flaws. Used as the foil for "steel is great and joins well" argument.

Then there's material selection — which brings me to another handout, The Future of Metals. Back in the early 90s the ceramists were telling the world that everything would be made of ceramics in the future. In the beginning of the world — and Shannon could attest to this, she's in archaeology — everything was made out of ceramics. They made pottery, and cement a few years later. But we got away from ceramics, and one of the reasons is they have lousy fracture toughness. The ceramists didn't understand that. This was the 1980s — what did they know about fracture toughness in the ceramics business in 1980 or 85? They knew nothing. That was one of the tragedies. They spent hundreds of millions of dollars trying to build all-ceramic internal combustion engines. The metals business said, huh. It made no sense, but they were getting all the research money. "Oh, we don't have any corrosion." Actually ceramics do corrode. It takes a little chloride and most of the ceramics are toast, and the critical flaw size is smaller than the width of a piece of paper.