Micro Welding Small Parts Using Fiber Lasers

The increasing complexity of micro-electronics, medical, and engineering devices has placed stringent demands on assembly techniques. A particular challenge facing manufacturers is how to achieve the power levels necessary to micro weld accurately without distortion.  

An effective way to weld very small parts is by using fiber lasers. Research carried out by JK Lasers demonstrates how excellent beam quality, low power (100W to 200W) continuous wave (CW) fiber lasers with modulation consistently achieve high quality spot welds on thin stainless steel foils (20μm to 150 μm). 

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 fiber 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’ fiber 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 Lasers is a global company that provides innovative industrial lasers and laser processing solutions for the medical device, aerospace, automotive, electronics and semiconductor industries. With decades of industry knowledge and an extensive portfolio of highly successful lasers, JK Lasers helps manufacturers choose the most suitable solution for their cutting, welding and drilling requirements. For further information please visit www.jklasers.com