Incoloy 909 help.

[rlgalli]

I have a couple of questions regarding Incoloy 909. This is the first time I have worked with this specific alloy. I am planning on annealing it in a hydrogen atmosphere. Is this material subject to hydrogen embrittlement? Also what acid ratio should I pickle it in? I know this is an uncommon alloy but I hope someone can help. Thank you.

 

[metengr]

My suggestion is to visit the web site below and contact Special Metals directly. I have dealt with them in the past and they know Ni-base alloys better than anyone

http://www.specialmetals.com/index.php

 

[metengr]

Is this material subject to hydrogen embrittlement?

No (see page 5 of the technical bulletin).

 

[Helicopterjunky]

Inco 909 has a very low,(less than half) of conventional superalloys Coefficient of Thermal Expansion (CTE). The material is often used in high temperature jet engine applications. Because it has no Chromium, it has poor general surface oxidation resistance as well as suffers from a condition known as Stress Assisted Grain Boundary Oxidation which can lead to transverse stress notch rupture sensitivity. The onset of this is just above 900F. This material also exhibits a drop-off in mechanical properties at 1200F due to instability of Gamma Prime. This material is weldable to itself and to other superalloys. Usage at or above 1000F typically requires coating with NiCrAlY alone or in conjunction with YZr topcoat. Heat treatments are specialized as is coating so seek professional advise as metengr suggested. One good thing is that there is quite a bit published on the characteristics of this material and it's earlier versions 903 and 907.