With the jewelry industry’s acceptance and increased use of new 950 palladium alloys for jewelry design and manufacturing, it’s fundamental to have a general understanding of related casting procedures.
In this installment of the 950 palladium jewelry manufacturing series of articles, Teresa Frye’, president of TechForm Advanced Casting Technology shares an overview of her company’s 950 palladium casting procedures and gives insight into the scientific approach they have undertaken to improve results.
TechForm has been casting platinum, palladium and stainless steel for 12 years for the jewelry, medical and aerospace industries. They recently shifted their focus to casting for the jewelry industry.
Photo by Sarah Loveland.
Design and Model Tips
Gates and the Investment Procedure
Inspection and Quality Control
|After the castings have been thoroughly cleaned, TechForm team members perform a variety of inspections. The inspection process begins with a loupe. Here Frye’ is looking for defects that may include cracking, porosity or no-fill. TechForm places a tab at the end of every tree arrangement. The tab is for ductility (stress) testing and is bent back and forth to test the resulting as-cast condition of the metal. Results are strictly recorded as are all key steps in each casting process, for purposes of research and accountability.|
|TechForm will periodically use an ultraviolet light and a chemical solution to inspect cast pieces for imperfections. The piece is submerged in the solution and then placed under the light in a dark environment. In this image, the process reveals a small void in the surface of a ring (arrow) which fluoresces a yellow-green color. This process is highly sensitive and can detect very small defects not visible to the naked eye in natural light.|
Finishing and Preparation
|When voids are located, TechForm uses an in-house laser welder with 30 gauge round 950 TruPd palladium wire to fill the voided areas.|
|After all quality inspections have been completed, the palladium pieces are processed for customer delivery. Kathleen Sullivan begins by removing the gates and little or no evidence of their placement is visible when she’s completed the process. This is an advantage to the customer because TechForm charges for their casting service based upon labor and the final weight that’s shipped out. Customers receiving their cast products from TechFrom encounter little or no waste due to gate removal.|
Photo by Sarah Loveland
|At TechForm, there is a production meeting each morning where Frye’ and her staff discuss previous day’s cast results and whether any corrective action is needed. In addition, the upcoming casting for the day is reviewed and team members collaborate about the details.|
|TechForm is located in a hub of world class casting companies serving a wide variety of industries. This location gives TechForm immediate access to casting consultation and testing facilities. Because hardness is a key indicator for wear resistance, Frye’ wanted an expert determination for her cast palladium sample. Here, a technician at Koon-Hall-Adrian Metallurgical uses high tech equipment and ConfiDent hardness testing software to gauge the as-cast Vickers hardness of a palladium alloy. The sample was mounted in a test block, polished perfectly flat, tested in 5 areas (recorded as planar readings in microns) and then analyzed by a technician. Test blocks are traceable with serial numbers to ensure clients of the reliability of their findings. Frye’ uses a range of testing services, including X-rays of cast pieces, to verify fixed production processes as well as a tool for her research of palladium alloys.|
Platinum and palladium casters agree that palladium has unique casting characteristics that differ from its sister metal platinum. TechForm has been leading the way in research and development of cast palladium jewelry products. TechForm is currently testing several new alloys recently introduced to the market for as-cast Vickers hardness, casting fluidity, metal working and polishing characteristics. Watch this series of articles for the latest palladium manufacturing updates.