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Medical Device Welding: Is Resistance or Laser Welding Better?

2022-09-07

Medical device welding is an important step to ensure components in their respective products are firmly and seamlessly joined for the expected life of the item. Resistance welding and laser welding are two of the most common techniques used in the sector. Here are some things people should consider before choosing one of these methods.

A Laser-Welding Innovation for Devices Made With Ceramics

Ceramics are of particular interest in the medical device sector because they are biocompatible and shatter-resistant. These qualities make them suitable for applications such as biomedical implants. However, until recently, ceramics have been challenging to weld because traditional methods require putting the pieces in furnaces and exposing them to high temperatures, which can cause cracking.

However, a research team devised a method of joining ceramics with laser welding and eliminating the need for a furnace. The participants clarified that, before their innovation, there was no way to embed electronics into ceramics because the high temperatures would burn them.

This new method, called ultrafast pulsed laser welding, aims a series of short laser pulses at the area between two ceramic parts. This approach causes localized melting that allows the two pieces to join. However, the researchers had to optimize several aspects, such as the strength and duration of each pulse.

The researchers confirmed that the focused energy allowed heating only the necessary places along the ceramic. That allowed joining the ceramic pieces without damaging delicate embedded electronics. This research highlights the importance of considering the types of materials a medical device uses when choosing resistance welding or joining the materials with lasers.

Another ceramic-associated method under the umbrella of resistance welding is resistance brazing. However, it involves fusing metal and ceramic, which is slightly different from what these researchers did. In any case, understanding the materials used in any medical device product involving welding is essential for getting the best results.

Both Methods Used for Battery-Welding Needs

Successful medical device welding requires carefully considering many seemingly minute aspects that combine for positive outcomes. One of those is the welding cable’s ampacity, or the maximum current the line can transfer safely without overheating or shutting down. The engineering team behind a medical device’s creation must also consider how welding relates to the product’s battery power.

People have relied on resistance welding for more than the last four decades to put battery-related components in medical devices. During that period, manufacturers have benefitted from numerous improvements, including those that enhance weld quality and provide additional options.

However, laser welding is also an option, often preferred due to how people can focus the light source to extremely small diameters. This is also a no-contact, non-consumable method. One thing to remember is that laser welding is a slightly newer technique, introduced in the mid-1980s. Decision-makers who prefer the most established options for medical device welding may choose non-laser types for that reason.

Digital Twins Can Contrast Resistance Welding and Laser Welding

Even people with extensive experience in resistance and laser welding sometimes find it challenging to choose the best method for their medical device projects. Fortunately, a digital twin could help fill in the gaps by allowing them to virtually recreate the expected results before trying a method in real life.

A digital twin is not the same as a simulation but allows people to study numerous complex processes simultaneously. Medical device manufacturing is particularly well-suited to digital twins because of the innovation required for companies to remain successful. It provides a relatively safe way for makers to clarify what works and what doesn’t.

Perhaps a company initially manufactured a device by prioritizing resistance welding. Would using a laser provide better quality assurance, lower costs, or another benefit? A digital twin lets people see the likely outcomes of changing the welding method. The virtualized environment helps them learn about pros and cons they might not have otherwise considered.

It’s becoming more common for metalworking shops to invest in digital twin technology. By doing so, people at these facilities can test different approaches without putting time and money into what could become real-life failures. A digital twin does not prevent things from going wrong but can make mistakes less likely.

In one case, researchers developed a twin to investigate and enhance the safety of collaborative robotic welding. Since that’s a relatively new option, the ability to try things in the digital realm first could prevent dangerous or costly consequences. However, it could also help people determine whether resistance welding or laser welding is better for a particular medical device or application.

No Definitive Answer for All Medical Device Welding Cases

Doing medical device welding well requires careful thought and attention to all aspects. It’s too short-sighted to say that laser-based welding is always best or that people should primarily prioritize resistance welding to get their needs met. However, decision-makers will be in the best position to make the most informed choices when they’re well aware of all the specifics associated with a particular device or the needs of the patient who will use it.

Article source: MPO