30+ Years of Precision Instruments
"Gene optimization" of platinum resistance (Pt100/Pt1000)
High-purity platinum wire (>99.999%): Zone melting is used to purify the platinum, thereby reducing resistance drift caused by impurities at grain boundaries.
Stress-Relief Annealing Process: Platinum wires are annealed in an inert atmosphere at 1000°C for 72 hours to eliminate cold-working residual stresses (residual stress can cause an annual drift of up to 0.03°C in resistance).
Ceramic Substrate Matching: Alumina/zirconia substrates are selected, whose coefficient of thermal expansion (CTE = 7 × 10⁻⁶/°C) is highly compatible with platinum (CTE = 9 × 10⁻⁶/°C), thereby preventing thermal cycling-induced microcracking.
Zero-stress design of package structure
Suspension lead: A platinum wire is freely suspended in an Ω-shaped configuration within a ceramic tube, isolating it from the transmission of mechanical stress (reducing drift by 90% in vibration environments).
Nanometer Magnesium Oxide Insulating Filler: A highly thermally conductive insulating powder (thermal conductivity >40 W/m·K) is filled between the platinum wire and the sheath, providing rapid heat conduction while also mitigating thermal shock stress.
| top ; padding-bottom: 10px; border-bottom-width: 0.8px; border-bottom-color: rgb(187, 187, 187); border-top: none; font-size: 15px; line-height: 1.72; border-right-color: rgb(187, 187, 187); border-left text; 187, 187, 187;"> Control points | stability contribution | |
|---|---|---|
| Cleanroom Enclosure | Class 100, humidity <1% RH | Stop resistance drift caused by moisture adsorption |
| Laser Sealing | helium mass leak detection (leak rate <10 and Pa · m³/s) | Intrusion of oxygen into oxidized platinum wire |
| gradient annealing | 200 ℃ → 800 ℃, 2 hours per step | Release package residual stress |
