Overview
IEC 62137-1-2:2007 - Surface mounting technology: Environmental and endurance test methods for surface mount solder joint - Part 1-2: Shear strength test - defines a standardized shear-type mechanical test to evaluate the endurance of solder joints between component terminals and lands on a substrate. The method is applicable primarily to leadless surface-mount components and surface-mount connectors where pull testing is not applicable. It is explicitly not intended for multi‑lead components (e.g., QFN, LGA) or gull‑wing leads.
Key topics and requirements
- Scope & purpose: Evaluate solder joint strength after environmental stresses, especially rapid change of temperature (temperature cycling), to assess durability of surface mount solder joints.
- Test equipment: Requirements for shear test equipment, a flat pushing tool, optical microscope (≈50X–250X, ~2 000 lx illumination) and scanning electron microscope (SEM) capabilities (3–10 nm probe), and a reflow soldering oven for mounting.
- Test substrate & mounting: Typical substrate defined (epoxide woven glass laminate, nominal 1.6 mm thickness, copper foil ≈0.035 mm) and recommended land geometry per IEC guidance or component supplier data.
- Test procedure elements: Pre‑conditioning, initial shear strength measurement, exposure to rapid temperature change, recovery, and intermediate/final shear strength measurements; control of displacement rate, shear height, and precise positioning of the pushing tool.
- Failure analysis: Defined areas for evaluation (solder, intermetallic compound layers, plated layers, substrate land) and documented failure modes to determine joint integrity.
- Reporting: Items to include in the test report and product specification to ensure reproducibility and traceability.
Practical applications and users
Who uses IEC 62137-1-2:2007:
- PCB and electronic assembly engineers validating surface mount solder joint reliability
- Quality, reliability and failure analysis teams performing environmental endurance testing
- Component and connector manufacturers demonstrating solder joint robustness for leadless parts
- Test laboratories offering standardized shear strength testing services
Why it matters:
- Helps assess the impact of temperature cycling and reflow processes on solder joint mechanical integrity.
- Supports design decisions for lead‑free vs. tin‑lead solders, land geometry, and assembly process optimization.
- Provides repeatable, comparable data for product qualification, supplier evaluation, and reliability demonstrations.
Related standards
Keywords: IEC 62137-1-2:2007, shear strength test, surface mount solder joint, surface mounting technology, leadless components, temperature cycling, reflow soldering, solder joint reliability.