Abstract
Purpose - The purpose of Part I is the manufacturing of the SAC 305 solder paste with multiwall carbon nanotubes (MWCNT) before and after their structure modification and also the influence investigation of the added carbon nanotubes on the technological properties and the microstructure of the "nano" solder pastes. This work is a continuation of similar previous studies of the SAC solders paste with a silver nanopowder addition.Design/methodology/approach - The authors applied the functionalization and esterification methods for the modification of the structure of the carbon nanotubes. The "nano" solder paste preparation was performed with the use of the two stage dispersion method of carbon nanotubes in the own manufactured SAC 305 solder paste. For the technological properties of the "nano" solder paste, the authors applied the slump, solder ball wetting and spreading tests, according to the existing standards. The standard metallographic procedures were applied for the microstructure analysis. Findings - As expected on the basis of the previous studies on the SAC solder paste with silver nanopowders, the Authors obtained positive results related to the own manufactured SAC 305 solder paste with carbon nanotubes by means of the dispersion method. Also applied were the functionalization and esterification methods, whose results showed microstructure changes in the carbon nanotubes. The "nano" SAC solder pastes show a positive influence on the slump property, compared to the basic SAC solder paste. The authors proved a negative influence of the carbon nanotubes addition (dependent on their concentration) on the spreading and wetting of the SAC solder paste on a copper substrate, which provokes the non-wetting and dewetting phenomena. A slightly improvement was found for the "nano" SAC solder pastes with modified carbon nanotubes. The carbon nanotubes’ presence in the solder paste demonstrates the positive effect of the reduction of the growth of the IMCs’ thickness, which depends on their type.Research limitations/implications - It is intended (the purpose of Part II) to verify the reinforcement effect of the alloys with carbon nanotubes suggested in the literature. For this purpose, we are going to carry out an assembly process of the RC electronic elements on PCBs with Ni/Au and SAC (HASL) finishes, using the SAC 305 solder paste with modified carbon nanotubes, for reflow soldering and next measure the mechanical strength of the solder joints and their microstructure.Practical implications - It is suggested that further studies of the reliability of solder joints are necessary for a practical implementation of the "nano" SAC solder pastes, but taking into account the wetting data, we should perform the investigation only for the "nano" pastes with the lowest addition of the modified carbon nanotubes. Originality/value - The "nano" solder paste’s preparation method by the two stage dispersion of carbon nanotubes in the own manufactured SAC 305 solder paste and the comparison study of the properties of the "nano" pastes with the basic SAC solder paste.
Purpose - The purpose of Part I is the manufacturing of the SAC 305 solder paste with multiwall carbon nanotubes (MWCNT) before and after their structure modification and also the influence investigation of the added carbon nanotubes on the technological properties and the microstructure of the "nano" solder pastes. This work is a continuation of similar previous studies of the SAC solders paste with a silver nanopowder addition.Design/methodology/approach - The authors applied the functionalization and esterification methods for the modification of the structure of the carbon nanotubes. The "nano" solder paste preparation was performed with the use of the two stage dispersion method of carbon nanotubes in the own manufactured SAC 305 solder paste. For the technological properties of the "nano" solder paste, the authors applied the slump, solder ball wetting and spreading tests, according to the existing standards. The standard metallographic procedures were applied for the microstructure analysis. Findings - As expected on the basis of the previous studies on the SAC solder paste with silver nanopowders, the Authors obtained positive results related to the own manufactured SAC 305 solder paste with carbon nanotubes by means of the dispersion method. Also applied were the functionalization and esterification methods, whose results showed microstructure changes in the carbon nanotubes. The "nano" SAC solder pastes show a positive influence on the slump property, compared to the basic SAC solder paste. The authors proved a negative influence of the carbon nanotubes addition (dependent on their concentration) on the spreading and wetting of the SAC solder paste on a copper substrate, which provokes the non-wetting and dewetting phenomena. A slightly improvement was found for the "nano" SAC solder pastes with modified carbon nanotubes. The carbon nanotubes’ presence in the solder paste demonstrates the positive effect of the reduction of the growth of the IMCs’ thickness, which depends on their type.Research limitations/implications - It is intended (the purpose of Part II) to verify the reinforcement effect of the alloys with carbon nanotubes suggested in the literature. For this purpose, we are going to carry out an assembly process of the RC electronic elements on PCBs with Ni/Au and SAC (HASL) finishes, using the SAC 305 solder paste with modified carbon nanotubes, for reflow soldering and next measure the mechanical strength of the solder joints and their microstructure.Practical implications - It is suggested that further studies of the reliability of solder joints are necessary for a practical implementation of the "nano" SAC solder pastes, but taking into account the wetting data, we should perform the investigation only for the "nano" pastes with the lowest addition of the modified carbon nanotubes. Originality/value - The "nano" solder paste’s preparation method by the two stage dispersion of carbon nanotubes in the own manufactured SAC 305 solder paste and the comparison study of the properties of the "nano" pastes with the basic SAC solder paste.