I.A. Lozovoy, A.V. Turetsky

Quality of solder connections in modern radio equipment has paramount value as the main reasons for refusals consist just in defiance of integrity of assembly connection. Various CAM-of system are widely applied to the analysis of designs on mechanical influences. These are such as NASTRAN, ANSYS, T-FLEX, PRO/Engineer, etc. If process of modeling doesn't cause special difficulties, the analysis of results of calculation is a complex challenge, which under force to only the highly specialized engineer having a wide experience in design of designs. Besides in these systems possibility of modeling of change of conductivity of solder connection depending on mechanical loadings isn't provided. The matter is that reliability of solder connection depends on many factors, in particular, from extent of preparation of surfaces under process of the soldering, structure and phase structure of accustomed to drinking materials, a roughness of a surface, a type of solder, grain size etc. Each of these indicators as in separateness, and everything together can affect size of conductivity of solder connection. Therefore for forecasting of durability of solder contacts without natural experiments not to manage. It is offered in the course of design of radio-electronic modules by standard means of CAM to settle an invoice on mechanical durability, and criteria of violation of integrity of solder connections to receive from experiments. In this case results of modeling will come nearer to the real. In spite of the fact that the most part of the specified standards on testing of assembly connections is devoted to SMD components, tests of the components mounted in an opening also is an actual task as modern without the lead solders considerably concede according to the characteristics traditional. The description of a technique of testing of solder connections of pin conclusions is provided. Thus having carried out the specified tests it is possible to receive critical values of mechanical loadings of solder contacts of components mounted in an opening depending on type of the case, a type of solder, technology of the soldering and so forth. These values can come in handy in the analysis of results of modeling of radio-electronic modules in CAM systems. If the component with the same type of the case gets to most mechanically loaded area on a payment, and it has no margin of safety, it is necessary to optimize a design.