Hi Allan,
once again a hearty thanks for replying!
Well, honestly I am no expert in grinding but the first time I have experienced that this detail might be considered as being a concern was when I have SMA welded parts of an annealing furnace using 36Ni/16Cr (~ E330) stick electrodes.
I was instructed at that time to use sulfur free grinding wheels for avoiding any undesired sulfur input. That was new for me as well, that time. As I was interested in this detail I have tried to find out (the Internet wasn't born yet) if there is any criterion for the recognition of these wheels. The only item was and is still today that the sulfur free discs had the admission of the German KWU (Kraftwerk Union) which was a SIEMENS subsidiary leading in the construction of many nuclear power plants. This special "KWU" admission stood and stands for highest product quality of each tool being used in mechanical engineering, just as a "knightly accolade".
I suppose that this statement doesn't really answer your kind question. Thus I have tried to find out (thanks God the Internet is already born meanwhile :-)) to find any hints on this particular topic.
Please let me attach what I have found:
http://www.enotes.com/how-products-encyclopedia/grinding-wheelhttp://www.abrasiveproducts.net/Kasco/msds.htmhttp://www.qqma.com/en/cpdetail.asp?id=7768Hmm, finally I personally would say that even by "normally" not knowing what kinds of constituents were used for producing a grinding wheel, one should "normally" presume that sulfur containing ingredients can be present.
In really critical applications I would thus "trust" the data sheets of the grinding wheel supplier, which is in Germany a bit easier as I suppose. Since in Germany we can explicitly have a search for even the "KWU admission" guaranteeing that no (or lowest) sulfur, iron and chloride contents could be measured.
Hope that I could shed some light on it.
My best regards,
Stephan