Oil Cavity Volumetric Expansion Mitigation in Piezoresistive Transducers
Minimizing fluid volume below five microliters and matching diaphragm spring rate eliminates thermal zero shift in isolated piezoresistive pressure cells.
Tantalum Diaphragm
Alloy Membrane
A thin metal foil made from a highly corrosion-resistant refractory metal protects pressure sensors from aggressive process fluids. Using a tantalum diaphragm provides a barrier against acids, chlorine, and other hazardous chemicals that would quickly destroy standard stainless steel foils. This protective barrier allows the sensor to operate in the most demanding industrial environments.
Chemical Resistance
The material forms a stable, protective oxide layer that resists chemical attack from strong acids and hot corrosive solutions. This oxide layer prevents corrosion and pitting, which would otherwise lead to pinhole leaks and sensor failure. This excellent resistance is why this metal is specified for chemical reactors and corrosive transport lines.
Pressure Transmission
Despite its resistance, the metal remains highly flexible, allowing it to transmit pressure changes to the internal fill fluid with minimal loss of sensitivity. The thickness of the foil is kept to a minimum to ensure that it does not restrict the sensor’s response or introduce non-linearities. This flexibility is critical for accurate measurements in both pressure and vacuum applications, ensuring that the sensor responds quickly to dynamic process changes without lagging.
Industrial Service
Transmitters equipped with these protective foils are widely used in chemical plants, paper mills, and pharmaceutical manufacturing facilities. Although these foils are more expensive than standard steel, the long service life they provide makes them a cost-effective choice for harsh processes. This durability reduces the need for frequent replacement and minimizes the risk of process downtime.