I haven't seen any micrographs that confirm that fact. You can see that 19C27 and Niolox have somewhat intermediate carbide volumes, though Niolox carbides may be somewhat smaller because of the niobium addition. However, in these calculations, JMatPro predicts lower carbide volume for 14C28N. Speaking to Sandvik, they said that 14C28N has a little bit higher carbide volume than 13C26, they said that they knew they were at the edge of the carbide volume range for avoiding primary carbides. Here are some low carbide stainless steels: Based on these numbers we would expect these steels to have comparable toughness but the V grades would have superior wear resistance because of harder MC carbides. But as an approximation they're probably not too bad. Some are close and some are going to be off. None of these simulations should be taken as gospel.
The biggest deviation is 154CM, which is quite a bit higher in Crucible's numbers than the JMatPro calculations. The carbide numbers are actually pretty close. Here are the numbers I got for S35VN, S30V, 440C, and 154CM: The amount and type of carbide controls the wear resistance, toughness, and to some extent the size of the carbides.įirst let's check some numbers against known carbide volumes: [ Carbide Type and Volume The amount of Cr and Mo in solution tells you the nominal corrosion resistance, more Cr means better corrosion resistance. For example, the amount of carbon in austenite tells you approximately what hardness can be reached and the general proportion of lath to plate martensite. That tells you generally what properties you will have after quenching. I then pulled out carbide, C, Cr, and Mo wt pct at those temperature. I ran these simulations at and around the common austenitizing temperatures used for these grades. That being said I have some data for you. These simulations come primarily from empirical data which may not be applicable to different combinations of alloys, especially rarely used elements used together and in high amounts. These are often not shown in equilibrium calculations because they aren't supposed to be there anymore. With high alloy steels, there are often large primary carbides left over from casting that are very difficult to get rid of through future processing. Much of heat treatment is used to specifically not reach equilibrium (i.e. It assumes that the steel is at equilibrium (the most stable state) which is often reached very slowly.
There are a variety of limitations to this method here are some of those limitations: You can learn a little about how these programs work on this site (I am not affiliated): [ You can use these programs to calculate the equilibrium phase fraction and wt pct in each phase. I had some fun today running some numbers through JMatPro, a thermodynamics simulation program similar to Thermo-Calc.