Wossner products are to be found in engines operating at the highest levels of motorsport competition and in everyday use –anywhere where longevity and operational noise are essential factors. Wossner products are the source of the superior power behind the success of well-known motor sport teams at national and international race meets. Wossner forged pistons are engineered for high performance and reliability, using premium materials and manufacturing methods. For this application, Wossner has added a hard coat anodize treatment to the piston to enhance the piston's ability to manage heat and wear. This technical bulletin is provided to help you understand how this treatment offers enhanced performance. Hardcoat anodizing is applied to the piston during the manufacturing process, and this is near the last step before the piston is finished and turned, ring pins are installed, and the wrist pin hole is honed. The treatment is converting the base aluminum material, which protrudes into the base material and is slightly above the surface. This conversion is known as an "anodic oxide layer" and forms a hardened surface that will improve the piston's crown and ring's land hardness and oil retention while preventing ring micro-welding.
Why is this important to the piston:
The piston crown requires additional protection from thermal distress, such as in engines with forced induction, heavy/constant thermal loads, or varied load environments.
The treatment will enhance the piston's ability to absorb operating temperatures or even sudden increases in temperature due to the state of tune, fuel quality, or load increases that are not immediately compensated for.
Ring groove wear is improved due to the treatment's ability to handle additional sliding wear compared to nontreated surfaces.
Ring micro-welding is the effect of aluminum material transferring from the piston ring groove to the ring under high-stress environments, causing the ring to no longer move freely and seal combustion. Mico-welding is eliminated when the ring groove is treated with hard coat anodize, providing an environment where the ring can operate appropriately under extreme conditions (REF SAE 960745).
Hardcoat anodize facts:
Has been tested and proven to improve thermal diffusivity by up to 10%
The treatment is inert and can handle temperature spikes of up to 2000C for brief periods
