IBE enables the world’s best brands. Through our unrivalled customer-centric approach, we partner with leading companies in numerous markets to deliver solutions for their most complex challenges.


IBe Industry Building, ShenZhen, China



PCB/PCBA knowledge
How to cope with high failure rate during soldering process

An automobile manufacturing plant where they use soldering techniques to assemble the bodies or components of vehicles. Sometimes, there are some situations that may occur that lead to high failure rate in the soldering process. For example, material quality problems due to the poor quality soldering materials, soldering electrodes containing impurities, or failure to meet the specified strength requirements.

In this article, we will discuss what the high soldering failure rate is and the reasons that cause the high soldering failure rate, and the solutions for high soldering failure rate.

Table of Contents

What is the high soldering failure rate?

High soldering failure rate refers to the occurrence of a large number of soldering defects or substandard solder joints during the soldering process. Soldering defects include but are not limited to porosity, cracks, slag inclusions, lack of fusion, weak welds, etc. A high soldering failure rate may cause the following effects.

1.Quality problem
High failure rate in the soldering process will directly lead to a decline in the quality of the solder joint. Soldering joints may have weak welds, pores, cracks, deformation and other defects, which will affect the mechanical properties and reliability of welded joints. This may cause the welded joint to break, crack or fail easily during use, affecting the performance and life of the entire welded structure or product.

2.Reduced productivity
High failure rates can lead to repeated soldering, repairs or rework during the soldering process. This will result in decreased production efficiency, increased production costs and time costs. Additional manpower, material and equipment inputs are required to repair or redo welded joints, slowing down production schedules and increasing lead times.

3.Increased maintenance and repair costs
High failure rates will lead to more frequent exposure and occurrence of quality problems in welded joints. This will increase maintenance and repair costs, including rework, rewelding or replacement of welded joints. In some cases, failure of solder joints may also cause damage to other components, further increasing maintenance and repair costs.

4.Increased safety risks
High failure rate during the soldering process may cause potential safety hazards. Substandard quality of welded joints may lead to insufficient structural strength to withstand rated loads or external stresses.

Also read: Reflow Soldering vs Wave Soldering – An In-depth Guide

What causes high soldering failure rate?

What causes high welding failure rate
What causes high welding failure rate

The following are some factors that may cause a high soldering failure rate.

01 Poor design and preparation
The quality and stability of the soldering process depend to a large extent on the design and preparation of the welded joint. If the design is unreasonable or the preparation is insufficient, it will lead to a decrease in the quality of the welded joints, thereby increasing the failure rate. For example, unreasonable or improper handling of welded joint geometry, material selection, surface treatment can bring negatively affect on welding quality.

Also read: What’s the type of PCB surface treatment?

02 Poor operating technique
The technical level and operation technique of welding operators play a vital role in soldering quality. Lack of necessary technical training or inexperience may lead to increased failure rates during the soldering process. Many detailed operations in the welding process, such as the control of current, voltage, welding speed, and welding angle, require operators to have a high level of technical skills and experience.

03 Insufficient quality control
Lack of effective quality control measures is another root cause of high failure rates during welding. Quality control in the soldering process includes the implementation of strict operating specifications, reasonable welding parameter settings, real-time monitoring and testing of the soldering process, etc.

How to solve the high soldering failure?

Some soldering mistakes and how to slove

There are some measures to cope with the high soldering failure rate.

1.Good design and preparation
Before proceeding with soldering, ensure adequate design and preparation. This includes selecting appropriate soldering methods and equipment, rationally planning the welding sequence and geometry of the welded joint, and ensuring the quality and suitability of soldering materials.

2.Material selection and preparation
Select the appropriate welding material and ensure its quality meets the requirements. Before soldering, materials should be properly cleaned, surface treated and preheated to improve the quality and reliability of welded joints.

3.Quality control and testing
Establish effective quality control measures including real-time monitoring and testing of the welding process. Use appropriate non-destructive and destructive inspection methods, such as X-ray inspection, ultrasonic inspection, eddy current inspection to find and eliminate potential welding defects.

Also read: Exploring PCBA X-ray inspection – An optimal method to detect the hidden defects

4.Soldering parameter optimization
According to the requirements of soldering materials and joints, the soldering parameters should be optimized. This includes the selection of parameters such as welding current, voltage, speed, temperature to ensure that the heat input and energy distribution during the welding process meet the requirements.

5.Maintenance and maintenance
Regular inspection and maintenance of soldering equipment to ensure its normal operation and stable performance. Regularly calibrate and maintain soldering robots, power supplies, electrodes and other components to improve the consistency and stability of the welding process.

6.Data Analysis and Improvement
Collect data from the soldering process, analyze and evaluate it. Through the monitoring and analysis of soldering data, identify potential problems and improvement opportunities, and take appropriate measures to correct and optimize the soldering process.


Manual soldering, a traditional PCB soldering method, is a process to heat and melt solder onto metal components, circuit boards or other parts to create a bond or electrical junction by hands.

  • Poor design and preparation
  • Poor operating technique
  • Insufficient quality control

  • Good design and preparation
  • Material selection and preparation
  • Quality control and testing
  • Soldering parameter optimization
  • Maintenance and maintenance
  • Data Analysis and Improvement

Leave a comment

Your email address will not be published. Required fields are marked *