Exhaust Valve Material?
Exhaust Valve Material?
(OP)
Hi,
I conducted a spectrometer tests on the failure exhaust valve which the standard material is unknown. i managed to get the result below:
C=0.78 ; Si=0.243; Mn=8.850; Cr=18.32; Mo=0.152; Ni=2.3; Cu=0.155; v=0.07; w=0.081.
Can somebody help me to find the reference standard for this material?
I conducted a spectrometer tests on the failure exhaust valve which the standard material is unknown. i managed to get the result below:
C=0.78 ; Si=0.243; Mn=8.850; Cr=18.32; Mo=0.152; Ni=2.3; Cu=0.155; v=0.07; w=0.081.
Can somebody help me to find the reference standard for this material?





RE: Exhaust Valve Material?
C 0.50-0.60
Mn 7-10
Cr 19.5-21.5
Ni 1.5-2.75
RE: Exhaust Valve Material?
Actually there are a lot of result but some one told me to select only this value...therefore i post that result only. What is the important material to highlight if we do not know the standards?
RE: Exhaust Valve Material?
RE: Exhaust Valve Material?
Did the head break off.
Some other failure altogether?
RE: Exhaust Valve Material?
to make it clear below are the detail:
C=0.78 ; Si=0.243; Mn=8.850; Cr=18.32; Mo=0.152; Ni=2.3; Cu=0.155; v=0.07; w=0.081; P=0.0236; S=0.0124; Al=0.002; Co=0.042; Nb=0.0532;Ti=0.0129; Pb=0.038; Sn=0.0109; Mg=0.0137; As=0.0024; Ca=0.0011; Ce=0.0144; Sb=0.0161; Te=0.0066; B=0.0041; Zn=0.0373; La=0.0017; Fe=68.7
There is no burn sign on the sealing face. However, the valve is cracked from the edge to center.
RE: Exhaust Valve Material?
What kind of engine was this in?
How old? Made where?
You also have to be careful doing chemistries because many valves are plated or coated.
There have been dozens of proprietary alloys used over the years.
The problem with your chemistry is that the C is too high, and the Mn and/or Ni too low for the alloy to be austenitic.
At the same time the Mn is too high for a ferritic stainless.
8440: Medium to heavy duty steel alloy with a higher chromium content to enhance high temperature strength.
Sil 1: Heavy duty steel alloy with an 8.5% chromium content for excellent high temperature performance. Used for many factory high performance intake valves.
Sil XB: A ferritic stainless steel alloy, with 20% chromium content and 1.3% nickel. Used in heavy duty intake valves.
422: A stainless steel alloy specified for high performance intake valve usage. This specialty type of stainless is designed with the temperature ranges and characteristics of intake valves usage in mind, and is different from the more common exhaust valve stainless materials.
21-2N: Austenitic stainless steel with 21% chromium and 2% NICKEL. As the most popular exhaust valve material, it has excellent performance characteristics at elevated temperatures. With additional heat treating and manufacturing processes, this material can be upgraded to become the ultimate choice for exhaust usage. With different processes, it makes for a good quality, inexpensive intake valve as well.
21-4N: An Austenitic stainless steel similar to 21-2N, except for a greater nickel content (4%), used as an alternate to 21-2N.
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Plymouth Tube
RE: Exhaust Valve Material?
RE: Exhaust Valve Material?
The story of a totally unexpected valve failure ( breakage, not cracking) is aboout half way down the page here -
http://www.vv.corvair.org/Library/benzinger.htm
Toward the end of the paragraph that starts "The turbocharger is not only interesting to me... "