From: vince@offshore.ai (Vincent Cate) Newsgroups: sci.space.tech Subject: Re: Reentry without ablation or ceramics? References: <9186edb5.0305121517.3f7bfc4f@posting.google.com> NNTP-Posting-Host: 207.42.133.230 Message-ID: <9186edb5.0305152010.d27c97@posting.google.com> Michael J Wise wrote in message news:... > I thot that Inconel was good to way more than 2000 C? 1200 C is 2192 F, so you are probably thinking Fahrenheit. Here is a links with lots of high temperature alloys: http://www.haynesintl.com/hta.html By the way, when I say metal is only good up to about 1200 C, I mean normal commercial alloys of reasonable price. There are others. Metals at high temperatures have problems with oxidizing or loosing strength. Above 2000 only Re is strong and only Ir does not oxidize. So Re coated with Ir is one way to go: http://www.ultramet.com/oxidatio.htm Also, you can make a foam out of these high temperature metals: http://www.ultramet.com/foamtech.htm But these foams have to be like 20% density and the metal is like 10+ grams/cc, so it is not light. You could make a design where the nose was small and had really high temperatures, but the rest of the vehicle was a cone behind this and did not have such high temperatures. Then only the nose would have to have ablation or active cooling and maybe exotic metals. The stuff below looks like the a practical/durable ceramic heat shield to me: http://www.ultramet.com/u2000tps.htm http://www.ultramet.com/therm.htm http://www.ultramet.com/u2000.htm http://www.ultramet.com/u2000a.htm Anyone know of anything they like better? -- Vince