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  1. coreman73

    Need some help finding a calibration company able to cover the US and Singapore

    Thanks Ed. My goal is to find one company that could handle the calibrations of all our locations (TX, LA and Singapore).
  2. coreman73

    Need some help finding a calibration company able to cover the US and Singapore

    The company I work for has metallurgy/polymer labs in Texas, Louisiana and Singapore. Would anyone happen to know of a calibration company capable of handling calibrations in those parts of the world? The equipment is primarily metallurgical (tensile machines with mechanical/digital...
  3. coreman73

    How to select a steel grade for best machinability and tooling life?

    In general, what are the major factors that should be considered when trying to decide between different steel grades for the same application? For example, if I want to make a simple combination wrench and have to choose between 4047 and 5046 what should I base my decision on as it relates to...
  4. coreman73

    Strange cracks or laminations along beam of wrenches

    JConnBMKR, These go through several machining steps including soft vibe after forging. There is even an additional hard vibe step administered after heat treating to remove even more surface material. Unfortunately though, I don't believe these processes really remove enough material to get...
  5. coreman73

    Strange cracks or laminations along beam of wrenches

    Stanweld, I will make that suggestion to the plant that they need to consider removing all scale remnants as well as any laps and seams. I think though that if this problem continues then the material supplier will have to be changed for sure. brimstoner, The plant informed me that they have...
  6. coreman73

    Strange cracks or laminations along beam of wrenches

    Thanks again metengr, Yes, I do agree the most important thing is to take preventative measures. Of course, it's always nice to be able to pinpoint the origin of such defects. I've got a raw material auditing program established to try and catch these defects before they have a chance to reach...
  7. coreman73

    Strange cracks or laminations along beam of wrenches

    I was just informed that the billet is received as hot rolled bar stock. Bars are then cut down to billet lengths using cold shearing. No other work is done to the billets prior to hot forging. From this info, would it be much more possible that these defects are most likely rolled-in scale?
  8. coreman73

    Strange cracks or laminations along beam of wrenches

    Thanks metengr, I will try and find out what condition the billets were received in from the material supplier and if they were rolled by working prior to forging. Just for the sake of comparison, I've attached some unrelated photos of a billet I was asked to examine recently and found what...
  9. coreman73

    Strange cracks or laminations along beam of wrenches

    I have received a couple of wrenches that are showing the as-titled surface defects. These wrenches are in finished condition and were made from steel grade 4047. Steel and hardness results meet spec. After microscopic examination, I found some defects that are outlined by a thin decarb...
  10. coreman73

    Failure analysis of ratchet

    A big thanks to all that posted. Brimstoner, Ok so the thin, dark etched layer beneath the surface is just related to the oxide (?) inclusions and not anything to do with decarb? That brings up another point of confusion for me. I have seen and been advised that forge cracks or forge...
  11. coreman73

    Failure analysis of ratchet

    Thanks Redpicker. I always look forward to your responses. That does make a solid case for forging lap. As decarb showing up during etching, maybe I don't understand something. I was under the impression that decarb layers would show up as lightly colored in contrast to surrounding areas...
  12. coreman73

    Failure analysis of ratchet

    Thanks Brimstoner. 1) I considered forging at first due to the corner being so heavily oxided and the appearance on the fracture surface. I thought that if it was a forging crack though that I would have been able to see a decarburized layer. My etching didn't show any sign of decarb at all...
  13. coreman73

    Failure analysis of ratchet

    I've received two Craftsman 1/2" drive teardrop ratchets in finished/plated condition that experienced premature failure during routine torque test. Both failed at the same site located at the fork. Results so far: 1. Bulk hardness of 46-48 HRC meets spec (40-48 HRC) 2. Chemical composition...
  14. coreman73

    Failure analysis of cracked pliers

    Thanks metengr. I guess there's no way to really determine where exactly it originated from since this part has been heat treated.
  15. coreman73

    Failure analysis of cracked pliers

    Just out of curiosity, I have a few questions about the decarb layer. What are some possible places it could have come from? Could it have only been formed during austenitizing? Did an earlier heat treatment step (i.e. forging, annealing) introduce it? Could it have come from the raw material?
  16. coreman73

    Ferrite or austenite grains: which is required for this application?

    rp, Thank you for yet another excellent response. It was very helpful to have it explained that way. I'm jealous of your knowledge. brimstoner, Thank you. That makes sense that we'd need fine grains to improve formability.
  17. coreman73

    Ferrite or austenite grains: which is required for this application?

    I am trying to determine which type of grain structure (either ferritic fine as rolled grain or austenitic fine grain by application of correct steel making composition) needs to be included in a specification for AISI 1045. This steel will be used to make hand tools, which will be formed using...
  18. coreman73

    Failure analysis of cracked pliers

    redpicker and swall, Thank you both again for all the valuable information.
  19. coreman73

    Failure analysis of cracked pliers

    redpicker, Yes, I'm seeing roughly 0.007" decarb on the outside surfaces away from the flash trim line. Considering this along with still not seeing any decarb at all along crack paths pretty much rules out forging cracks entirely. You have given me lots of valuable information to use as...
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