Material Compatibility Evaluation of High-Power Interconnects For Single-Phase Immersion Cooling

Author: Presenter (on behalf of Vishwash Harish and Northera India Design Team) Collection: 2023 Global Summit - Cooling Environments

Summary

This presentation reports on material compatibility and reliability testing of high-power interconnects for single-phase immersion cooling, with the goal of identifying what changes are needed to adapt the EIA-364 connector reliability standard for the immersion environment. Two connectors were tested—an ORv3 IT Gear Input Connector and an "extreme power" connector—in two fluid types: a synthetic PAO (polyalphaolefin) and a fluorocarbon. The key finding for current capacity is consistent with other workstream reports: connectors can carry approximately twice the rated air current in fluid at the same 30°C temperature rise threshold, and all tested reliability sequences passed. However, the deeper contribution of this work is identifying which EIA-364 test sequences are inapplicable, inappropriate, or unadaptable to the immersion environment, and calling on the community to engage IEC, EIA, and UL to develop immersion-specific standards.

The study systematically worked through EIA-364-1000's six environmental test groups in fluid. Two groups (temperature life and thermal shock) were successfully adapted with minor modifications. Two groups (mixed flowing gas/MFG and dust) were deemed inapplicable because the failure modes they target—contact corrosion from atmospheric gases and particulate accumulation—do not occur in fluid. Two groups (vibration and another thermal cycling sequence) present procedural challenges not yet resolved. The critical gap is that even the test sequences that can be run in fluid use acceleration factors derived from air (e.g., 105°C/240 hours = 65°C/10 years), and those relationships are not validated for immersion environments. The community does not yet know whether 80°C accelerated immersion exposure for 21 days corresponds to 1 year, 5 years, or 20 years of in-service life.