Micro welding small parts using fibre lasers

The increasing complexity of micro-electronics, medical, and engineering devices has placed stringent demands on assembly techniques. Fibre lasers are increasingly used by Asian manufacturers to accurately process different material types and thicknesses. A particular challenge facing manufacturers is how to achieve the power levels necessary to micro weld accurately without distortion. In a competitive global marketplace, it is imperative that they accelerate throughput, while maintaining quality and minimising costs.
 An effective way to weld very small parts is by using fibre lasers. Research carried out by JK Lasers demonstrates how excellent beam quality, low power (100-200W) continuous wave (CW) fibre lasers with modulation consistently achieve high-quality spot welds on thin stainless steel foils (20μm–150μm). With a wide range of Watt to kilowatt fibre lasers, JK Lasers is perfectly positioned to meet this demand.
Used in the manufacture of hard disk drive flexure arms, these foils help to hold ferrite readers above spinning magnetic media. The high positioning speed and ultra-close proximity of the ferrite reader mean flexure arms must be accurately assembled. Their design must accommodate resonances, stiffness and overall component accuracy in three planes. Spatter-free welds are critical to ensuring the reliable operation of hard disk drives. Any brittle oxide or melt spatter on the surface may flake-off and contaminate the drive, rendering it useless.
During JK Lasers' trials, a single mode fibre laser with Gaussian beam profile produced spatter-free spot welds between 76μm and 175μm in diameter. A flat top beam profile, available as an optional feature in JK Lasers' fibre laser range, achieved spatter-free welds between 150μm and 270μm in diameter. The high levels of accuracy achievable using JK Lasers' modulated CW lasers enable high quality, shallow conduction mode spot welding with excellent top bead profile that are tailored to the target.

JK Fiber Lasers
JK Fiber Lasers offer exceptional beam quality and stable high power levels from the moment they're switched on. As a result, they can achieve smaller spot sizes or the same focused spot size with a greater stand-off distance compared to Nd:YAG and CO2 lasers.
These inherent laser qualities are supported by JK Lasers' patented FiberView software, which gives operators complete control over the laser. At the touch of a button, laser parameters and pulse shapes can be programmed, processes can be monitored, and data can be captured for analysis.
JK Fiber Lasers are further enhanced by the company's bespoke process tools, which comprise cutting and welding heads, re-collimation units, focus lens modules and welding air knives. Designed to operate in perfect synergy with the JK Laser range, these tools are low maintenance and modular in design so packages can be tailored to every need.
There are many applications in Asia, and indeed around the world, where highly reflective materials such as aluminium, copper, brass and even gold, must be processed. In these instances, there is the risk that laser light can be reflected back, causing fibre damage.
To manage this risk, JK Lasers has developed patented back reflection protection integrated into its fibre optic beam delivery, which safely channels reflected light away from sensitive areas. If the back reflection exceeds acceptable limits, JK Lasers' closed-loop monitoring system triggers an automatic shutdown, protecting the laser from potentially costly damage.
 With a mean time to failure (MTTF) of over 300,00Air More Uptempo