摘要:
The present invention provides a printed circuit board that can suppress the positional displacement of parts mounted thereon. The printed circuit board includes resist formed on the surface of the printed circuit board, lands for receiving respective parts to be mounted, the lands being arranged off openings free from the resist, and lands for alignment, respectively alignment marks being formed on the land for alignment by means of solder.
摘要:
The invention relates to a sintered alloy. This sintered alloy includes 3-13.4 wt % of W, 0.4-5.6 wt % or 0.8-5.9 wt % of V, 0.2-5.6 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, 0.6-2.2 wt % of C, and a balance of Fe. The sintered alloy includes first and second phase which are distributed therein, in a form of spots, respectively. The second phase is in an amount of from 20 to 80 wt %, based on the total weight of the first and second phases. The first phase contains 3-7 wt % of W, 0.5-1.5 wt % of optional V, up to 1 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, up to 2.2 wt % of C, and a balance of Fe. The second phase contains 3-15 wt % of W, 2-7 wt % of V, 1-7 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, up to 2.2 wt % of C, and a balance of Fe. When the manganese contents of the first and second phases and the total of the sintered alloy are respectively in a range of from 0.2 to 1.0 wt %, sulfur is respectively contained therein in an amount of from 0.1 to 0.6 wt %. The sintered alloy has wear-resistant at high temperature and good compatibility without damaging mating part that is in contact with the sintered alloy.
摘要:
The present invention provides a printed circuit board that can suppress the positional displacement of parts mounted thereon. The printed circuit board includes resist formed on the surface of the printed circuit board, lands for receiving respective parts to be mounted, the lands being arranged off openings free from the resist, and lands for alignment, respectively alignment marks being formed on the land for alignment by means of solder.