X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmmtao105.cox.net ([68.230.241.41] verified) by logan.com (CommuniGate Pro SMTP 5.2.5) with ESMTP id 3041155 for flyrotary@lancaironline.net; Thu, 24 Jul 2008 20:01:20 -0400 Received-SPF: none receiver=logan.com; client-ip=68.230.241.41; envelope-from=alventures@cox.net Received: from fed1rmimpo02.cox.net ([70.169.32.72]) by fed1rmmtao105.cox.net (InterMail vM.7.08.02.01 201-2186-121-102-20070209) with ESMTP id <20080725000042.OPGD774.fed1rmmtao105.cox.net@fed1rmimpo02.cox.net> for ; Thu, 24 Jul 2008 20:00:42 -0400 Received: from BigAl ([72.192.137.74]) by fed1rmimpo02.cox.net with bizsmtp id u00a1Z0051cVYgg0400aMU; Thu, 24 Jul 2008 20:00:42 -0400 From: "Al Gietzen" To: "'Rotary motors in aircraft'" Subject: Inconel Date: Thu, 24 Jul 2008 17:02:10 -0800 Message-ID: <000001c8edf2$10ec9db0$6401a8c0@BigAl> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C8EDAF.02C95DB0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C8EDAF.02C95DB0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable There are at least a dozen alloy variations in the inconel family, with differing mechanical properties. I have never heard of H-25 alloy; but presumably a variation of 625. Perhaps not the best choice for = properties, but is one of the more weldable. Hard to find fatigue data on the = alloys, but many, including 625 work-harden (related to fatigue failure) quite rapidly making them difficult to machine. =20 I don't know which alloy was used for my manifold/muffler, but the guy = that made it for me got the material from Boeing. He thought it was 694 or = 718; both of which are more common in the aerospace industry. Just playing = with a scrap it seemed to be quite malleable at room temperature. What ever = it is, he did a very nice job of welding and it is doing nicely on my = engine at 120 hours. =20 =20 I'd agree; at 1500F the best bet is 321 SS. At 1700F I'd go with = inconel to avoid stress corrosion; but even then with thick walls, low stress, 321 = can work. =20 Al =20 -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Greg Ward Sent: Thursday, July 24, 2008 2:41 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: exhaust building =20 It (H-25) fatigues early at lower temps. That's why all the Nascar = types have stopped using it, because they run around 1500 deg. or so, and got tired of spending about 5 times the money for header failures. Greg ----- Original Message -----=20 From: Al Gietzen =20 To: Rotary motors in aircraft=20 Sent: Thursday, July 24, 2008 11:55 AM Subject: [FlyRotary] Re: exhaust building =20 Iconel, on the=20 other hand is overkill. It lives at 2000+ degrees, and doesn't like it = at=20 lower temps, and will degrade, plus it's very expensive. =20 Brad; =20 Yes, inconel tolerates temps of 2000+, but explain what is "and doesn't = like it at=20 lower temps". That sounds strange to me. =20 Al G ------=_NextPart_000_0001_01C8EDAF.02C95DB0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

There are at least a dozen alloy variations in the inconel family, with differing mechanical properties. =  I have never heard of H-25 alloy; but presumably a variation of 625.  = Perhaps not the best choice for properties, but is one of the more weldable. = Hard to find fatigue data on the alloys, but many, including 625 work-harden = (related to fatigue failure) quite rapidly making them difficult to = machine.

 

I don’t know which alloy = was used for my manifold/muffler, but the guy that made it for me got the = material from Boeing.  He thought it was 694 or 718; both of which are more = common in the aerospace industry.  Just playing with a scrap it seemed to be = quite malleable at room temperature.  What ever it is, he did a very nice = job of welding and it is doing nicely on my engine at 120 hours.  =

 

I’d agree; at 1500F the = best bet is 321 SS.  At 1700F I’d go with inconel to avoid stress = corrosion; but even then with thick walls, low stress, 321 can = work.

 

Al

 

-----Original = Message-----
From: Rotary motors in = aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Greg Ward
Sent: Thursday, July 24, = 2008 2:41 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: = exhaust building

 

It (H-25) fatigues early at = lower temps.  That's why all the Nascar types have stopped using it, because they run around 1500 deg. or so, and got tired of spending about = 5 times the money for header failures.

Greg

=

----- Original Message = -----

From: Al = Gietzen

Sent: Thursday, July 24, 2008 11:55 AM

Subject: [FlyRotary] Re: exhaust building

 

Iconel, on the

other hand is overkill.  It lives at = 2000+ degrees, and doesn't like it at

lower temps, and will degrade, plus it's very expensive.

 

Brad;

 

Yes, inconel tolerates temps of 2000+, but explain what is = “and doesn't like it at

lower temps”.  That sounds strange = to me.

 

Al G

------=_NextPart_000_0001_01C8EDAF.02C95DB0--