NDT portable Device to measure the amount of Sigma Phase ?
NDT portable Device to measure the amount of Sigma Phase ?
(OP)
Hi everybody
I am looking for a NDT portable device to measure the Sigma Phase on a part made by an 310 AISI steel
Can anyone help
Thanks
I am looking for a NDT portable device to measure the Sigma Phase on a part made by an 310 AISI steel
Can anyone help
Thanks





RE: NDT portable Device to measure the amount of Sigma Phase ?
RE: NDT portable Device to measure the amount of Sigma Phase ?
In every case the presence of Sigma was verified by Metallurgical analysis.
RE: NDT portable Device to measure the amount of Sigma Phase ?
RE: NDT portable Device to measure the amount of Sigma Phase ?
You are forcing to to go way back (the late 50's) in time for this one. These measurements were made on the outlet manifolding on two stream methane reformers and some piping on a very large submerged combustion system. The H2 plant materials were HK40 tubes with 310HC SS manifolds and 316 SS laterals on the manifolds. All these welds carried a lot of Ferrite in the welds due to the inadequacy of the welding electrodes. I can't recall the numbers but they were very high and evidently the welds had been mapped as built(1952) and we measuring the loss of ferrite due to conversion of the ferrite to Sigma Phase. As I piece the process back together I think we may have been looking for low ferrite numbers. I can't get any verification of this as I'm about the only one left around. A I've stated before the rag pickers have got rid of all the old records and reports.
The submerged combustion unit had two problems, nitriding and Sigma Phase. It was all 316 SS welded by SMAW with very heavy welds due to the configuration.
RE: NDT portable Device to measure the amount of Sigma Phase ?
RE: NDT portable Device to measure the amount of Sigma Phase ?
My problem is to find a device to measure the amount of the sigma phase.
In fact we use an AISI 310 parts in our heat treatment shop and these parts break after a certain time due to the sigma phase precipitation.
I ma tying to optimise the chemical composition
But for the parts we have now in service we want to know the mount of the sigma phase with non destructive method.
The only non destructive method I found is to check the hardness with a portable device EQUOTYP because the safe part show à low hardness 170 HB and the broken parts show a high hardness 240-250 HB
RE: NDT portable Device to measure the amount of Sigma Phase ?
RE: NDT portable Device to measure the amount of Sigma Phase ?
I do not know of any portable devices to measure sigma phases. We have check it in the past only in laboratory with a ndt to check the volumic percentage.
luis
RE: NDT portable Device to measure the amount of Sigma Phase ?