Science of Soldering© Engineering Curriculum

All the Knowledge Tools That Ensure Success

Other soldering courses consist of nothing but lectures and memorization. But Science of Soldering© is genuine education. With experiments and demonstrations as well as comprehensive videos and a thorough workbook, the course explains the essential science, exposes the myths, and develops a powerful “recipe” for perfect soldering.

The course teaches by troubleshooting a multifaceted hands–on soldering process problem. In solving the problem (which involves several causes rather than a single root cause), the class learns the critical scientific forces that control all soldering from simple hand soldering to the most complex machine soldering. The class then develops quality and supplier management systems to prevent defects rather than allowing process mistakes and hoping inspection will find the defects.

And we'll roll up our sleeves to help you implement the new knowledge on the shop floor.

The following draft curriculum has been designed to meet the special needs of production, quality, design and supplier quality engineers. As with all Science of Soldering© classes, it can be modified to meet your specific needs and interests.

Part 1. The Science

1. The Core Science

  • Wetting forces
  • Chemical reactions
  • Intermetallic bonds

2. The Science of Soldering© Recipe

3. Clean Surfaces

  •  Definition and importance
  •  Contamination
  •  Oxides

4. Flux

  • Defined
  • Types and attributes
  • Acidity, ionic contamination and effects on reliability
  • The real definition of no–clean flux
  • Selecting fluxes suitable for high reliability applications

5. Solderability

  • Definition and importance
  • Solderability of different component and PCB surfaces
  • Implications of lead–free component finishes
  • Scientific solderability management

6. Solder

  • Defined
  • Alloys (leaded and lead–free)
  • Mechanical properties (ductility and tensility)
  • Lead–free solder differences and techniques

7. Heat

  • Why heat is needed
  • How much heat is needed
  • Failure modes from overheating
  • Scientific heat control and elimination of damage during hand soldering

8. Soldering vs. Welding

  • Definitions
  • Significance of surfaces that melt during “soldering” vs. surfaces that do not melt (the overlooked lead–free issue)
  • Uses of soldering and welding in electronics assembly

9. Troubleshooting Using the Science of Soldering© Recipe

10. Prevention of Heat Damage in Hand Soldering — The Electronics Manufacturing Sciences Solution

Part 2. Machine Soldering

1. Wave and Selective (Mini–Wave) Soldering

  • The Science of Soldering© Recipe in wave soldering
  • Physical forces determining machine setup
  • History of wave soldering evolution (and lessons for today)
  • Selecting flux
  • Selecting components
  • Role and effect of turbulent (chip) waves

     
  • Setting and managing wave profiles
  • Design for wave soldering
  • Techniques for maximizing process robustness
  • Mini–wave selective soldering
  • Palletized selective soldering
  • Dip selective soldering

2. Surface Mount Reflow

  • The Science of Soldering© Recipe in surface mount reflow
  • Basic concepts and history of process evolution
  • Selecting components and consumables
  • Design for reflow producibility
  • Stencils
  • Setting and managing oven profiles
  • Secrets of maximum process robustness

Part 3. Lead–Free Solders and Soldering

1. Choosing the Alloy

  • Available alloys
  • Physical properties and failure modes
  • Risks in extreme operating environments

     

2. Choosing Materials

  • Fluxes
  • Components
  • Laminates

3. Equipment Requirements

  • Heat
  • Ability to tolerate the alloys
  • Wave soldering machines
  • Surface mount reflow

4. Risk Assessment and Avoidance

5. Warranty Considerations

Part 4. Quality Systems and Reliability

1. Inspection and test strategies

  • Why visual criteria are not valid for reworked connections
  • Understanding the psychology of inspectors and the implications
  • 100% vs. sample inspection
  • Consequences for reliability

2. Reliability Criteria

  • The truth about “high reliability” soldering
  • What solder appearance reveals about machine soldering
  • What solder appearance reveals about hand soldering, repairs and rework
  • The strengths and weaknesses of A–610 and J-STD-001
  • How to identify reworked connections
  • Reliability criteria that work

3. Corrective Actions

  • Attacking the cause rather than the symptom
  • More inspection is not corrective action

4. Failures

  • Realistic product life expectancy
  • Common causes of failure and how to avoid them
  • Effects of thermal cycling on solder joint structure and reliability
  • The significance of regional failure patterns
  • Troubleshooting using the EMS Soldering Recipe and Reliability Criteria

Part 5. Open Discussion

Part 6. Shop Floor Implementation

The extent and length of this portion varies from project to project. The amount of Electronics Manufacturing Sciences involvement will be specified in the final quotation for services.

  • Role and effect of turbulent (chip) waves

     
  • Risks in extreme operating environments