Tin, lead and their alloys, due to their low melting temperatures and wide availability, are the most commonly used solder materials. In fact, lead has been used as a soldering metal for water pipes (also made of lead) even in Roman times, hence the scientific name for lead, Plumbum. Mechanical Properties.
hearing impairment - impairment of the sense of hearing. hearing disorder. disability, disablement, handicap, impairment - the condition of being unable to perform as a consequence of physical or mental unfitness; reading disability; hearing impairment. deafness, hearing loss - partial or complete loss of hearing.
A disorder in the ability to process information that can result in attention, perception, or memory. deficits; despite adequate hearing, vision, and intelligence, learning disabled students experience. difficulty in school learning. â¢ Academic needs: struggle with listening, reading, spelling, writing, etcâ¦.