Economy: Lower material cost translates into a less expensive chamber.
Full visibility: You can add windows to an aluminum chamber, but nothing beats the 360-degree visibility offered by acrylic.
Chemical resistance: Aluminum stands up to Spor-Klenz®, alcohol and other sterilants, making it preferable in many bio/pharmaceutical applications. In addition, because many joining and sealing compounds are designed for use with metals, they may degrade acrylic and result in leaks or chamber failure.
Greater machining versatility: Aluminum allows easier addition of feed-throughs to accommodate power and data cords, electrodes and other accessories. These add-ons are more feasible on aluminum than acrylic chambers, which are more prone to cracks that develop into leaks over time. For such applications, an aluminum chamber is a wiser long-term processing solution.
effective moisture barrier: Acrylic, because it is hygroscopic, allows moisture penetration on a
molecular level. Under vacuum, these water molecules are released from the
surface and may require several vacuum cycles to remove. These issues don’t
occur with aluminum and other metallic moisture barriers.
dimensional versatility: Due to greater strength, aluminum is more appropriate than acrylic for
larger chamber sizes.