Boeing DPS 9.76-1 Chisel Test Specimens

Chisel specimens for testing by Boeing DPS 9.76-1 §4.5.2 (Sulfamate Nickel Plating - Chisel Test). These heat treated chisel test specimens are made from steel round bar (4340 or 300M steel) and are heat treated to the test method requirements.
 
The ends of the chisel specimens are masked before plating. The plated coating is then tested by using a chisel along the edges of the machined notches and examining the nickel plating for failure (separation from the chisel specimen). These specimens, also referred to as heat-treated bar specimens, are reusable.