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.