Overview
IEC 62137-1-3:2008 is an international standard published by the International Electrotechnical Commission (IEC) that specifies environmental and endurance test methods focusing on surface mount solder joints. Part 1-3 of this standard covers the cyclic drop test method, designed to evaluate the mechanical strength and durability of solder joints between surface mounting device (SMD) terminals and land patterns on printed wiring boards (PWBs). This test is particularly relevant for larger multi-terminal components commonly found in handheld mobile devices and other portable electronics that are subject to repeated drops or impacts.
The cyclic drop test helps manufacturers assess and improve the robustness of solder joints by simulating real-world mechanical stresses, enabling better design and material choices for longer-lasting electronic assemblies.
Key Topics
- Scope: The standard applies specifically to solder joints in surface mounting technology, focusing on larger components prone to damage from drops.
- Test Description: It details procedures to cyclically drop a test substrate with mounted components to induce stress on solder joints, measuring impact strength and durability.
- Materials and Equipment:
- Reflow soldering oven with prescribed temperature profiles for consistent soldering quality.
- Dedicated drop impact test equipment, including substrate securing jigs and measurement instruments.
- Test substrates typically made from double-sided reinforced epoxy woven E-glass laminated sheets, as per IEC 61249-2-7.
- Measurement Methods: Use of strain gauges attached to the substrates to measure surface strain and maximum strain during drops, providing quantitative evaluation of joint performance.
- Evaluation Criteria: The number of drop cycles that lead to fracture or failure in the solder joint is recorded, supporting improvements in solder alloy, substrate design, and component mounting.
- Comparison of Solder Alloys: The standard highlights differences in mechanical properties between lead-free and tin-lead solder joints, emphasizing the need for tailored testing to select the optimal solder materials.
Applications
IEC 62137-1-3:2008 is critical for quality assurance and reliability testing in the manufacturing of electronic devices with surface mount technology, including:
- Handheld Mobile Devices: Smartphones, tablets, and other portable gadgets that are frequently dropped or subjected to mechanical shock.
- Consumer Electronics: Devices such as wearables, remote controls, and gaming consoles where solder joint integrity is essential for long-term performance.
- Automotive Electronics: Electronic control units and sensors requiring robust solder joints to withstand vibrations and impacts.
- Industrial Equipment: Electronics used in machinery that may experience cyclic shocks or drops during operation or handling.
- Research and Development: Engineers and designers use this standard to validate new solder alloys, substrate materials, and assembly methods for enhanced durability.
By adopting this test method, manufacturers can identify weak points in solder joint designs, optimize reflow soldering processes, and select materials that meet stringent endurance requirements.
Related Standards
IEC 62137-1-3:2008 is part of the broader IEC 62137 series on environmental and endurance test methods for surface mount solder joints. Important related standards include:
- IEC 60068-1: Environmental testing – General guidance applicable to testing environments.
- IEC 60194: Printed boards – Terms and definitions relevant to PWB and assembly.
- IEC 61249-2-7: Material specifications for printed boards including flammability and substrate characteristics.
- IEC 61190-1-2: Requirements for soldering pastes used in high-quality electronics assembly.
- IEC 61192-1: Workmanship requirements for soldered electronic assemblies.
- IEC 61760-1: Surface mounting technology – Specifications for SMD components.
- IEC 60068-2-27 and IEC 60068-2-31: Test methods focused on component robustness related to shock and drops.
Compliance with IEC 62137-1-3 along with these complementary standards ensures comprehensive evaluation of solder joint quality and assembly reliability for modern electronics manufacturing.
Implementing the cyclic drop test as defined in IEC 62137-1-3:2008 enhances the reliability of surface mount solder joints ensuring electronic devices can withstand the mechanical stresses typical in daily use - ultimately leading to higher customer satisfaction and reduced product failures.