Do I need it to be thermally conductive?.How long until the parts sets so I can move it?.Any shadow areas the light won’t reach?.Will the adhesive cure during the soldering process?.Provide electrical insulating properties to the SMD.ĭuring the course of engineering a board, certain questions need to be addressed in order to choose the right material:.Tack down wires to prevent stresses imposed on the part.Fully encapsulate and entire board or just an SMD to protect it from environmental factors such as moisture and chemical exposure.Be electrically conductive to attach components that would be damaged during the heat required for soldering.Be thermally conductive to transfer heat from the SMD onto a heat sink.Act as an underfill to protect the component from stresses caused by physical drops and/or thermal contraction and expansion.Provide strain relieve on the solder joint.Not only can adhesives be used to hold SMD’s in place our products can also: Permabond has developed products to make engineers lives a little easier. Many times these boards are double sided and require an adhesive to hold the parts in place on the bottom of the board as the top side is reflowed first.Īdhesives chemistries have developed alongside the rigid demands of the electronics industry to help alleviate some of the stresses caused by the new heat exposure, heat generation of the parts themselves and even drop shock of the end product as the demand for hand held devices grows. On the other hand, manufacturing utilizing re-flow ovens incorporated the thixotropic/green strength of the flux and solder paste mix. Not only was the temperature increase extreme for the individual components, it also created issues with the parts moving from the original placement of the board itself.Īdhesives have long been used to attach SMD’s to through-hole board as they travel through the reflow oven. Solder temperatures increased from 183 deg C to 217 deg C with certain parts of the board seeing even higher numbers.
REFLOW SOLDER OVEN FREE
Environmental regulations that have driven the industry to lead free technologies have added even more frustration to the mix. In today’s world, electrical engineers are charged with the challenging task of precisely filling an already densely populated PCB with even more components. Adhesives that withstand reflow soldering
0 kommentar(er)
