✅ List of Environmental & Reliability Tests in Electronics Manufacturing:

1. Thermal Cycling / Thermal Shock Test

2. High Temperature Operating Life (HTOL)

3. Temperature Humidity Bias (THB)

4. Highly Accelerated Life Test (HALT)

5. Highly Accelerated Stress Screening (HASS)

6. Salt Spray (Corrosion) Test

7. Vibration Test

8. Mechanical Shock Test

9. Drop Test

10. Dust and Water Ingress (IP Rating Test)

11. Burn-In Test

12. Electrostatic Discharge (ESD) Test

13. Power Cycling Test

14. UV Exposure Test

15. Altitude Test

16. Package Seal and Leakage Test (Hermeticity Test)

17. Board-Level Reliability (BLR) Testing

18. Solder Joint Reliability (SJR) Test

🔍 Detailed Explanation of Each Test

1. Thermal Cycling / Thermal Shock Test

• Purpose: To test PCB/component tolerance to temperature extremes.

• Method: Alternate exposure to high (e.g., +125°C) and low (e.g., -40°C) temperatures rapidly.

• Failure Mode: Cracked solder joints, material delamination, microfractures.

2. High Temperature Operating Life (HTOL)

• Purpose: To evaluate long-term reliability under heat while powered.

• Method: Operate the board at elevated temperatures (e.g., 125°C) under power for 1000+ hours.

• Failure Mode: Component degradation, early life failure.

3. Temperature Humidity Bias (THB)

• Purpose: To simulate hot and humid operational conditions with electrical bias.

• Method: Power applied during exposure to 85°C/85% RH for 1000 hours.

• Failure Mode: Leakage current, corrosion, dendritic growth.

4. Highly Accelerated Life Test (HALT)

• Purpose: To find design weaknesses before mass production.

• Method: Subject board to extreme temps, vibrations, and voltage stresses beyond specs.

• Failure Mode: Early wear-out mechanisms, latent faults.

5. Highly Accelerated Stress Screening (HASS)

• Purpose: Screen for production defects in early manufacturing lots.

• Method: Similar to HALT but applied to 100% of manufactured units at controlled levels.

• Failure Mode: Identifies defective units early.

6. Salt Spray (Corrosion) Test

• Purpose: Evaluate corrosion resistance of coating or metal components.

• Method: Expose PCB to continuous mist of 5% NaCl solution for 96–240 hours.

• Failure Mode: Corrosion, conductive paths, connector failure.

7. Vibration Test

• Purpose: Assess mechanical robustness against vibrational forces (automotive, aerospace, etc.).

• Method: Apply vibration in X, Y, Z axes at defined frequencies and amplitudes.

• Failure Mode: Connector loosening, cracked solder joints.

8. Mechanical Shock Test

• Purpose: Simulate impact forces during drop, shipping, or mechanical handling.

• Method: Apply sudden acceleration/deceleration (e.g., 50–1500 g) in milliseconds.

• Failure Mode: Cracked boards, dislodged components.

9. Drop Test

• Purpose: Simulate accidental drops during consumer use.

• Method: Drop product from a defined height (1–1.5 m) on hard surfaces at multiple angles.

• Failure Mode: Casing cracks, PCB misalignment, breakage.

10. Dust and Water Ingress (IP Rating Test)

• Purpose: Determine IP rating (Ingress Protection).

• Method: Expose products to dust (IP5x/6x) or water jets/submersion (IPx5/7/8).

• Failure Mode: Liquid/dust intrusion, corrosion, short circuits.

11. Burn-In Test

• Purpose: Eliminate early failures (infant mortality) by stressing the board under load.

• Method: Run PCB at elevated temp (e.g., 70–100°C) and voltage for 24–168 hours.

• Failure Mode: Early component failures, solder joint cracks.

12. Electrostatic Discharge (ESD) Test

• Purpose: Simulate static electricity discharges to assess component resilience.

• Method: Use Human Body Model (HBM), Machine Model (MM), or IEC 61000-4-2 standards.

• Failure Mode: IC internal damage, communication faults.

13. Power Cycling Test

• Purpose: Assess reliability under repeated power ON/OFF cycles.

• Method: Automatically turn device on/off at set intervals for hundreds/thousands of cycles.

• Failure Mode: Power supply or capacitor failures.

14. UV Exposure Test

• Purpose: For products exposed to sunlight – tests plastic degradation or discoloration.

• Method: Continuous UV lamp exposure simulating weeks/months of sun.

• Failure Mode: Enclosure yellowing, material breakdown.

15. Altitude Test

• Purpose: Simulate operation/storage at high altitudes (low pressure).

• Method: Place product in vacuum chamber (e.g., 15,000–30,000 ft pressure).

• Failure Mode: Dielectric breakdown, capacitor expansion.

16. Package Seal and Leakage Test (Hermeticity)

• Purpose: Used for ICs or sealed packages in military/aerospace.

• Method: Helium leak detection under vacuum.

• Failure Mode: Moisture ingress, corrosion.

17. Board-Level Reliability (BLR) Testing

• Purpose: Reliability of solder joints and PCB materials.

• Method: Combine mechanical flexing + thermal cycling.

• Failure Mode: Pad lifting, solder cracks, delamination.

18. Solder Joint Reliability (SJR) Test

• Purpose: Validate solder strength and fatigue resistance.

• Method: Use temperature cycling (e.g., -40°C to +125°C for 1000+ cycles).

• Failure Mode: Intermetallic layer cracks, open joints.

📋 Summary Table