The Fundamental Role Of Solder Paste Printing In New Product Intro
Surface mount assembly (SMT) has a crucial role to experience in the Awesome Introduction (NPI) process for electronics manufacturing.
The high a higher level automation from the SMT methodology provides a variety of advantages, from automatic correction of errors, to simpler and faster assembly, better mechanical performance, increased production rates and reduced labour costs.
The SMT assembly process to have an electronics manufacturing services (EMS) provider can be separated into four key stages:
Solder Paste Printing
Pick and Place
Oven Profiling
Automated Optical Inspection (AOI)
With respect to the complexity of the design, or perhaps your own outsourcing strategy, your product or service could move across all these processes subsequently, or else you may find that you simply omit a measure or two.
You want to highlight the actual attributes, along with the vital importance, in the solder paste printing process to your NPI.
Working to your specifications
Step one on your EMS provider will be to analyse the pcb (PCB) data which is specific for your order, in order that they choose the required stencil thickness as well as the the most suitable material.
Solder paste printing is regarded as the common method of applying solder paste with a PCB. Accurate solder paste application is hugely essential in avoiding assembly defects that may use a knock on effect further along the production process. So it is vital this key stage is correctly managed and controlled by your EMS partner.
Solder paste is essentially powdered solder that is suspended within a thick medium called flux. The flux provides a kind of temporary adhesive, holding the ingredients available before the soldering process begins. Solder paste is used for the PCB by using a stencil (generally stainless steel, but occasionally nickel,) then as soon as the solder is melted it forms an electrical/mechanical connection.
The thickness from the stencil is what determines the total number of solder applied. For some projects it may be important to have several thicknesses in different areas within the one stencil (often referred to as a multi-level stencil).
Another important element to take into consideration within the solder printing process is paste release. The proper sort of solder paste should be selected dependant on how big is the apertures (or holes) inside stencil. When the apertures are incredibly small, as an example, then the solder paste could be quite likely going to staying with the stencil instead of adhering correctly on the PCB.
Governing the rate of paste release however can be managed, either start by making changes to the design of the aperture or by reduction of the thickness in the stencil.
The type of solder paste utilized also can effect on the final top printing quality, therefore it is imperative that you select the appropriate mixture of solder sphere size and alloy for the project, and make sure it is mixed to the correct consistency before use.
Ensuring quality
When the stencil has become designed as well as your EMS partner is ready to make the first PCB, they'll next be considering machine settings.
Put simply, the flatter you can preserve the PCB through the printing process, better the outcome is going to be. So by fully supporting the PCB in the printing stage,either using automated tooling pins or which has a dedicated support plate, your EMS provider can take away the chance of any defects like poor paste deposit or smudging.
It's also important to take into account the speed and pressure from the squeegees during the printing process. One solution is going to be have one speed to the solder paste but to get varying degrees of pressure, using the unique specifications with the PCB along with the whole squeegee.
Cleansing the stencils, both ahead of and throughout production, is likewise essential in ensuring qc. Many automatic printing machines have a system that could be set to completely clean the stencil after a fixed quantity of prints which helps in order to avoid smudging, and prevents any blockages from the apertures.
Finally too, the printers needs to have a built-in inspection system (like Hawk-Eye optical inspection) that may be preset to evaluate the use of paste throughout the whole PCB after printing.
The solder paste printing process is really a precise and detailed one that may significant part to play within the ultimate success of your awesome. And, since this post highlights, a lot of detailed tasks are more likely to happen behind the curtain before your EMS partner solders the initial electronic aspect of a board.