| 摘要 |
THE PRESENT INVENTION PROVIDES A SURFACE TREATED STEEL SHEET FOR ELECTRONIC COMPONENTS SIMULTANEOUSLY SATISFYING THE SOLDER WETTABILITY, WHISKER-PROOF PROPERTY, AND STABILITY OF APPEARANCE WITH AGING WHILE NOT CONTAINING HAZARDOUS SUBSTANCES WITH ENVIRONMENTAL IMPACT SUCH AS LEAD AND CHROMIUM AND A METHOD OF PRODUCTION OF THE SAME, THAT IS, A SURFACE TREATED STEEL SHEET FOR ELECTRONIC COMPONENTS COMPRISING STEEL SHEET OR Ni PLATED STEEL SHEET PLATED WITH Sn AND Zn AND THEN TREATED BY THERMAL DIFFUSION OR PLATED WITH Sn-Zn ALLOY TO FORM AN Sn-Zn ALLOY LAYER, WHEREIN SAID Sn-Zn ALLOY LAYER IS DEPOSITED IN AN AMOUNT OF 3 G/M� OR MORE, THE Sn- Zn ALLOY LAYER HAS A Zn (WEIGHT)/Sn (WEIGHT) RATIO OF 0.001 TO 0.1, PREFERABLY 0.001 TO 0.01, AND THIS Sn-Zn. ALLOY LAYER HAS AN INORGANIC COATING MAINLY COMPRISED OF PHOSPHORIC ACID-ZINC-MAGNESIUM IN A P+Zn+Mg DEPOSITED AMOUNT OF 0.1 TO 100MG/M�, PREFERABLY 0.1 TO 10MG/M�. |
