Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations The Obturator on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

U-Factor

Status
Not open for further replies.

mahadhatu

Materials
Nov 4, 2003
65
While reading some specifications for Duplex Stainless Steel Castings and Forgings, I came accross the term "U-Factor". It says here that this factor is dependent on the weight percentage of Si, Cr and Mo.

Can somebody help me understand the significance of this factor and where else it might be used?

Thanks
 
Replies continue below

Recommended for you

Normally, U-factor refers to the heat transmissivity of a medium, and is the inverse of the R-factor


Alloying elements could well change the conductivity, hence the U-factor.

... although, by the way you described it, it doesn't sound like the correct definition for the context.

Anyway, good luck
 
kclim,

heres a relation that defines the U-factor

U = 4.76*Si + 2.65*Cr + 3.44*Mo - 43.64

I dont think this relation determines the conductivity in any way. There must be some other explaination.

thanks for your help
 
Time to send McGuire a wake-up call. Anyone know his number? <g>
 
The elements listed in the equation are ferrite stabilisers, although the constants don't match anything i've seen.

I found a similar equation to yours, although there are a lot more elements listed.


(near the bottom)

Km = Cr + 6 x (Si) + 8 x (Ti) + 4 x (Mo) + 2 x (Al) - 2 x (Mn) - 4 x (Ni) - 40 (C + N) - 20 x (P) - 5 x (Cu)

an equation regarding the balance between ferrite and martensite.

Hope that helps
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor