How to Select Potting Compound for Strain Gauge Pressure Sensors? ELAPLUS EP 2016 AB Flexible Epoxy Solution Reduces Stress and Improves Measurement Stability

The core of a strain gauge pressure sensor lies in its sensitive element, which captures tiny deformations and converts pressure variations into electrical signals. Such sensors are highly susceptible to structural stress. If the potting material is overly rigid, or generates excessive curing shrinkage and thermal stress, it will impose extra loads on strain gauges, solder joints, leads and sensitive cores, resulting in zero drift, fluctuating sensitivity and poor long-term measurement stability. Therefore, when choosing potting compounds for pressure sensors, hardness alone is not the key factor. Priority should be given to materials featuring flexibility and low stress, reliable adhesion, stable temperature resistance, contamination resistance, oil resistance and long-term fixation performance. For strain gauge pressure sensors, high-temperature resistant sensors, soft magnetic component potting and other applications, ELAPLUS Functional Materials (Shanghai) Co., Ltd. recommends the two-component flexible structural epoxy ELAPLUS EP 2016 A/B. According to the product datasheet, EP 2016 A/B is a two-part epoxy curable at room or elevated temperature, suitable for metal bonding, soft magnetic component encapsulation and high-temperature sensor potting. After curing, it delivers high mechanical strength, outstanding adhesion, wide temperature resistance and excellent contamination resistance. I. Why Overly Rigid Potting Materials Are Unsuitable for Strain Gauge Pressure Sensors A strain gauge pressure sensor generally consists of an elastic body, strain gauges, bridge circuit, leads, PCB, housing and sealing structure. During operation, the elastic body must produce consistent, repeatable micro-deformation. Hard potting materials will compromise product reliability in the following aspects: ■ Extra stress impairs measurement accuracy Strain gauges output signals by detecting minimal strain. Ultra-rigid potting compounds generate additional stress during curing shrinkage, thermal cycling or mechanical vibration, triggering sensor zero drift, unstable output or sensitivity deviation. ■ Thermal cycling causes interfacial tension Pressure sensors are widely deployed in automotive equipment, industrial machinery, hydraulic systems and engine oil pressure…