Don't forget about thinking about recovery rates. Granted this is only a 50g sample you are trying to make, but you should still consider recovery efficiency in determining the amount of raw alloy you are adding.
I would also like to remind everyone that the analysis of tramp elements would be very good for this determination. EAF's have only been around for a relatively short amount of time. Copper content should be relatively low in most older steels as they were likely produced through virgin iron...
Having worked in the auto industry for a while, removed nearly 5 years, I do not know of anything industry standard that is defined as B1. I think it pertains directly to your individual customer specification. I would go back to my customer to see if this is their internal specification that...
About 20 years ago I did my senior project looking at the interface between Titanium and Ceramic material using a Scanning Ultrasonic Microscope. This is testing my memory, but I recall during my orientation to the instrument one of the key things was it was able to detect the profile of an...
41XX series grades are highly suspectable to hydrogen flaking, especially when the bar cross sections gets larger. Vaccuum degassing is a must for this grade and in many cases a slow cooling to help in the removal of hydrogen. You should find out what kind of degassing cycle was run on this...
lidbasky,
There are several ways of controlling the amount of Nitrogen in the steel. First off your specification, you just need to specify how much you need. For your reference, BOF steels can typically have much lower Nitrogen content than EAF material. This has to do with how steel is...
metengr,
I think I phrased my statement incorrectly. What I was trying to find out was the austentizing procedure. A induction heated and quench and tempered product vs. a continuous/box furnace heat will produce different Charpy results.
TVP,
I'm a little confused by your statement about prior austenite grain size. The austenitic grain size is not going to change due to thermo-mechanical work. It is established during the casting/solidification of the material. I think you are looking at the ferritic grain size which can...
Personally, they look like sample prep defects. One question though, is this a transverse or longitudinal cross section relative to cast direction. DABwilldo mentioned MnS inclusions, if this were a longitudinal plane I would have to disagree with his assessment of MnS inclusions. They...
Under no circumstance should you be adding FeO to your slag. As the above poster has mentioned the addition of FeO will simply add oxygen to your system. Based on what you have described above, you are pouring open into an open tundish. The slag that you mention being "created after 3-4...
arunmrao (Materials) 19 Sep 09 21:36 wrote
Lower carbon or no carbon grades will obviously pose problems. You need to consider,other strong deoxidisers and perhaps inert gas purging in the melt to reduce your gas porosity.
Lower carbon steel grades 1006-1012 typically use medium carbon...
All:
A couple of key points I wouldl ike to add.
1) The Nitrogen being introduced after vacuum degassing will not help displace the hydrogen in the steel. At least not to appreciable amounts. Hydrogen would be removed to below 1ppm based on hydris testing after degassing operation.
2)...
Heavyforgings,
You can go about calculating 4340 Hardenability a couple of ways. I believe StelCalc works for 43XX grades of steel. Also if you are able to get your hands on an older copy of the actualy specification from Caterpillar 1E0038, they included their regression equations for...
redpicker,
I'm not sure he is asking for Q&T 5155/5160. It may be in the as-rolled condition for all we know. However, your suggestion of Nital/Picral will both work. I personally, like Picral, but to get grain sizes Nital would work better if you can get it to etch correctly. 2% Nital at...
Stanislasdz:
Having been in your predicament before I know exactly how you feel. The way I look at things when it comes to chemistry is to go back to the customer specification. If the customer has spec'd out Cr to 0.55 wt % as you have indicated then anything up to 0.554 is acceptable...
I'd just like to add my $0.02 worth.
Low Silicon steels, 0.10 wt % or lower are much more difficult to produce to a clean steel practice. Like was previously stated, Al is typically used as the only killing agent. In most cases, since melt shops are catch carbon, the steel is typically blown...
