IEC 61189-2-804:2023

Overview

IEC 61189-2-804:2023 is an international standard published by the International Electrotechnical Commission (IEC) that specifies test methods for determining the time to delamination of electrical materials, printed boards, and other interconnection structures and assemblies. Utilizing a Thermomechanical Analyser (TMA), this standard focuses on evaluating the thermal durability of base materials and printed circuit board (PCB) laminates under elevated temperature conditions-typically at 260 °C, 288 °C, and 300 °C. However, it allows flexibility in temperature selection based on specific testing requirements.

This standard is crucial for manufacturers, designers, and quality control professionals engaged in electronics assembly and materials testing, offering a reliable method to assess material integrity under thermomechanical stress and to predict the lifespan and reliability of PCB laminates.

Key Topics

• Test Method for Time to Delamination:
  Determination of the duration until the onset of delamination in PCB substrates or base materials when subjected to high-temperature conditions.

• Specimen Preparation and Requirements:
  Samples consist of unclad laminate materials or printed circuit boards, preferably from multilayer boards with internal conductors intact to assess bond integrity. Specimens are typically 6.35 mm by 6.35 mm, with smooth edges achieved through sanding to prevent mechanical stress.

• Equipment Specifications:

  • Thermomechanical Analyser (TMA) with dimensional change detection of ±0.001 mm
  • Drying chamber maintained at 105 °C ± 2 °C
  • Low humidity cabinet (<30 % RH, 23 °C)
  • Diamond cutting blade or equivalent for specimen preparation

• Test Procedure Summary:

  • Preconditioning specimens at 105 °C for 2 hours
  • Cooling to room temperature in low humidity conditions
  • Placing samples on TMA with a probe applying 49 mN force
  • Heating at a controlled rate of 10 °C/min until the target isothermal temperature is reached
  • Maintaining the temperature until measurable delamination occurs or for a maximum of 10 minutes

• Data Interpretation:
  Time to delamination is defined by irreversibly altered thickness detected through TMA, signaling failure. Notably, some materials may delaminate before reaching the isothermal temperature, in which case the failure temperature is recorded.

• Comprehensive Reporting:
  The test report delivers detailed information such as specimen description, environmental conditions, scan rates, observed failure times, and any deviations from the protocol.

Applications

IEC 61189-2-804:2023 is designed for practical use in multiple areas related to electronics manufacturing and materials science:

• Quality Assurance in PCB Manufacturing:
  Enables manufacturers to evaluate the adhesion integrity of laminates and whole PCBs, ensuring compliance with thermal reliability requirements.

• Material Selection and Development:
  Assists researchers and developers in characterizing new materials or laminates for enhanced heat resistance and durability.

• Failure Analysis:
  Provides baseline data to analyze delamination failures in thermally stressed assemblies, guiding remediation and design improvement.

• Process Optimization:
  Supports electronics assembly operations in refining soldering profiles and thermal processes to minimize delamination risk.

Related Standards

• IEC 60194-1: Vocabulary related to printed board design and electronic assembly technologies, referenced for terminology consistency in IEC 61189-2-804.
• IPC-TM-650 No. 2.4.24.1: A method for time to delamination testing using TMA, offering comparable methodologies primarily used in North America and industry-specific contexts.
• IEC 61189 Series: A comprehensive suite of international standards covering test methods for electrical materials, printed boards, and interconnection structures, facilitating holistic evaluation of electronic assemblies.

By adhering to the test methods outlined in IEC 61189-2-804:2023, stakeholders can achieve accurate assessment of delamination resistance, enabling enhanced reliability and longevity of printed circuit boards and electronic materials in high-temperature operating environments. This standard is an essential tool for ensuring quality and performance in modern electronics manufacturing.