Metal powders play a pivotal role across diverse industries, from aerospace to automotive electronics. Understanding their production processes and applications is crucial for optimizing their utility. In this article, we delve into the production and applications of bismuth powder, shedding light on its varied uses and benefits.
 
 

The Production Process of Bismuth Powder

The production involves intricate processes, notably the ball milling and atomization methods. Each method yields distinct particle shapes, distributions, and properties. While ball milling results in irregular particles with a wider distribution range and higher oxygen content, atomization produces spherical particles with uniform distribution and superior performance. Micro-nano bismuth powder, prepared through the condensation method, boasts high purity, sphericity, and specific surface area.
 
 

Specifications and Applications

Bismuth Powder finds applications across multiple industries, owing to its versatility. Available in various specifications such as -100 mesh, -200 mesh, -325 mesh, and -500 mesh, 200-325 mesh in interval particle size. It serves as a crucial component in metal alloys, metallurgical additives, protective products, lead substitutes and casting materials, etc.
 
 

Industrial Applications

In the metallurgical industry, it enhances the performance of cast iron, steel, and aluminum alloys by improving cutting performance, refining crystalline organization, and reducing sintering temperatures. Moreover, its use in protection and ceramics industries, driven by demands such as ROHS certification, replaces lead materials effectively.
 
 

Specialized Applications 

  • When it is added to solder paste in soldering material, which contains 64% tin, 35% bismuth, and 1% silver, it has a melting point of 180°C and an operating temperature of 200 ~ 220°C (time 120 ~ 180 seconds). It is widely used for CPU heat sinks and heat sink modules due to the improved manufacturing yield from operation at moderate temperatures.
  • When it is processed into nano and ultra-fine particles, it can be used as lubrication additives: adding 0.1-0.5% micro-nano bismuth powder to the lubricating grease, it can make the surface of the friction partner form a self-lubricating and self-repairing film during friction, and improve the performance of the lubricating grease.
  • When it is added in high temperature solder paste which requires higher temperature when passing through the furnace. The melting point is more than 79 ℃ higher than Sn / Bi solder paste. The main component is tin, silver and copper, and the melting point is more than 217 ℃ – 227 ℃. Widely used, good weldability, hard and firm, good mechanical strength and bright solder joint.
  • Added to low-temperature lead-free solder paste, in which the tin content is 42% and the addition amount of bismuth powder reaches 58%. The main component is tin bismuth. After adding bismuth powder to the solder paste, the temperature will drop, and its melting point will be 138 ℃. It is suitable for components or PCBs that cannot withstand high temperature. Low temperature solder paste has relatively poor weldability, brittle solder joints and dim luster.The melting point of this solder paste is 138 ℃, which is suitable for reflow soldering process with high requirements. This solder paste is suitable for some low-temperature electrical devices, with superior wettability and welding performance, especially for the welding of LED circuit board. 
 
 

Advantages and Future Prospects

The unique properties of bismuth powder, coupled with its diverse applications, present significant advantages across industries. As technologies evolve and environmental regulations tighten, the demand for bismuth powder as a sustainable alternative is poised to rise, driving innovation and expanding its utility further.
 
 

Conclusion

Bismuth Powder emerges as a versatile and indispensable material, offering a myriad of applications across industries. From its production processes to specialized applications, its significance continues to grow, promising advancements in various fields. As we navigate towards a sustainable future, bismuth powder stands at the forefront, unlocking new possibilities and driving innovation.