Adhesion and attaching of particles at the failed connector contacts

Adhesion of particles and the attaching of particles on contact surfaces are two of the major problems for the simulation test on contact failure caused by dust particles. Based on the inspection of electric contact failure of mobile phone used in China, it is found that the adhesion of particles are mainly caused by organic materials such as sodium lactate and other chemicals from the sweat. Particles tightly attach on contact surface can be caused by various factors; corrosion products trap the dust particles could be one of the important reasons. This paper identifies the sodium lactate and other materials found at failed contacts of mobile phones and describes its contribution to the failure. With the support of experimental result it also evidentially describe the trapping effect of the corrosion products. This paper could be of use to improve the simulation dust test for mobile phone used in China.