We receive many questions about working with palladium and decided to ask Linus Droggs, an industry expert, to offer some techniques for palladium casting.

Palladium casting processes and techniques are very similar to the other high melting temperature metals — platinum and stainless steel.

The most asked question I hear is: Can palladium alloy be cast with torch melting? The quick answer is no. Palladium can be successfully cast with traditional centrifugal methods, but because of palladium's physical properties, it cannot be torch melted.

Here are a few other tips about casting with palladium:

• Palladium absorbs large amounts of oxygen and hydrogen during melting. Induction melting with an addition of vacuum and inert gas protection will shield palladium and prevent it from becoming contaminated with atmospheric gases. It is recommended to evacuate the casting chamber and back fill it with argon three times before melting to ensure that the majority of harmful gases have been removed before the melting cycle begins
• Phosphate-bonded investment is required due to the high melting temperature
• ZO paint is recommend to treat a fused silica crucible prior to melting to reduce the cross contamination producing inclusion defects.
• Almost all the plaster can be removed with a high-pressure water blast due to a thin oxide layer formed on the cast tree during melting.
• Palladium melts at a slightly lower temperature than platinum, which helps to reduce investment vitrification during casting. So a mild investment remover can dissolve the remaining plaster residue.
• After a thorough cleaning to neutralize any residual chemicals the casting can be processed like any other jewelry alloy.

Good housekeeping procedures should be used to ensure consistent results and successful returns.