Micro Coaxial Cable factory

Methods for Aging Detection in Micro Coaxial Cables

1. ‌Electrical Performance Degradation Analysis‌
   ‌A. Insertion Loss and Return Loss Monitoring‌
   ‌Baseline vs. Aged Comparison‌:

Frequency (GHz) New Cable (dB/m) Aged (5 years, 10k cycles)
10 0.42 0.68 (+62%)
30 1.15 2.10 (+83%)
60 2.40 4.50 (+88%)
Aging causes dielectric breakdown and conductor oxidation, increasing loss.
‌Tool‌: Vector Network Analyzer (VNA) with ±0.05 dB accuracy (e.g., Keysight PNA).

‌B. Time-Domain Reflectometry (TDR)‌
‌Fault Localization‌: Detects impedance mismatches from shield corrosion or connector wear.
‌Case Study‌: A 0.8mm cable in a radar module showed a 15% impedance drop at 12cm, indicating cracked dielectric after thermal shock testing.

2. ‌Material Property Evaluation‌
   ‌A. Dielectric Spectroscopy‌
   ‌Key Metrics‌:
   ‌Dissipation Factor (tan δ)‌: Increases from 0.0003 to 0.0015 in PTFE after UV exposure.
   ‌Permittivity Drift‌: ±2% variation in εᵣ accelerates phase instability.
   ‌Method‌: LCR meters (e.g., Hioki IM3536) measure dielectric response at 1 MHz–1 GHz.
   ‌B. Thermogravimetric Analysis (TGA)‌
   ‌Degradation Temperature‌:
   ‌Virgin FEP Insulation‌: 380°C.
   ‌Aged FEP (500 thermal cycles)‌: 345°C (-9.2%).
   ‌Application‌: Identifies polymer chain scission due to overheating.
3. ‌Mechanical Stress Testing‌
   ‌A. Flexure Endurance‌
   ‌Test Protocol‌: IEC 61196-1 dynamic bending (radius = 5× diameter).
   Cable Diameter Cycles to Failure (20% ΔZ)
   0.32mm 8,000
   1.2mm 25,000
   Smaller cables fatigue faster due to higher stress per bend.
   ‌B. Tensile Strength Measurement‌
   ‌Failure Threshold‌:
   ‌New‌: 50N (braided shield).
   ‌Corroded (salt fog test)‌: 28N (-44%).
   ‌Tool‌: Instron 5967 dual-column tester.
4. ‌Environmental Aging Simulations‌
   ‌A. Thermal Cycling‌
   ‌Condition‌: -55°C ↔ +125°C, 1,000 cycles (MIL-STD-883H).
   ‌Result‌: Microcracks in ETFE jackets reduce shielding effectiveness (SE) from 90 dB to 65 dB.
   ‌B. Humidity Exposure‌
   ‌Test‌: 85°C/85% RH, 1,000 hours (JESD22-A101).
   ‌Consequence‌: Silver-plated conductors show >50% tarnish (Ag₂S), raising resistance by 30%.
5. ‌Advanced Non-Destructive Techniques‌
   ‌A. Terahertz Imaging‌
   ‌Resolution‌: 10μm defects in dielectric layers.
   ‌Case Study‌: THz scans detected delamination in 0.47mm cables used for 5G mmWave arrays before electrical failure.
   ‌B. AI-Powered Predictive Maintenance‌
   ‌Model Inputs‌: Historical loss data, bend cycles, thermal profiles.
   ‌Output‌: Predicts remaining useful life (RUL) with >90% accuracy (Siemens Senseye®).
6. ‌Industry-Specific Standards‌
   Standard Focus Area Acceptable Aging Threshold
   IEC 61196-1 Flexure and RF performance <15% insertion loss increase
   MIL-DTL-87104 Thermal/chemical resistance No visible jacket cracks
   Automotive USCAR 2 Vibration durability <10% impedance drift
7. ‌Case Study: Aerospace Cable Aging Mitigation‌
   ‌Problem‌: Shield braid fractures in 0.5mm cables caused intermittent CAN bus errors in satellites.
   ‌Solution‌:
   TDR identified fracture locations.
   Replaced with Au-plated cables (MIL-DTL-17 qualification).
   Implemented 6-monthly VNA-based screening.
   ‌Outcome‌: Zero aging-related failures in 3 years.