The heat capacity of the involved materials affects the ultimate temperature achieved when the materials come in contact. Since the initial conditions of the tissue are somewhat fixed, it is important that the anvil have a high heat capacity, high mass and low temperature in order to have the lowest ending temperature possible. In our case, however, the tissue controls the results because it's thermal conductivity is very low relative to that of any anvil material. Here are the significant thermal properties of copper and several materials that don't oxidize too rapidly at room temperature. Diamond conducts heat away from the sample 6 times as fast as copper.
Diamond absorbs twice as much heat as copper per degree of temperature change.
DDK has made cryo anvils with single crystal diamond inserts for several different slamming devices. These anvils were placed in the field for evaluation and experimental results have demonstrated the advantages outlined above. The durability of our copper-diamond bond is shown by the hundreds of impacts it has survived. Because of the limited sizes of single crystal diamond available, a slamming area of 4mm square is the largest practical. The new CVD diamond film technology is another approach but the ability to grow films on copper, film adhesion and particle size are all problems not yet resolved.