Material Properties of Stainless Steel: What does It mean for Stencil Manufacturers?
New challenges in the stencil industry, including ever decreasing component size and increasing legislation, have made the selection criteria for stencil base materials ever more important This paper focuses on some important qualities of the base material for stencils to be taken into consideration when deciding upon the best material for an SMT stencil.The most common used types of metal for stencil fabrication were tested here: Stainless Steel (302/304), Datum HDX (a Ni and Cr enriched stainless), Datum PhD (304 Stainless with specific finishes for the SMT industry) and Electroformed Nickel sheets. Experiments were performed to measure flatness, stencil durability, paste contamination, capability of depositing paste for 0201 technology, wettability, paste release and achievable aspect ratios for paste release. To gain a fair representation for these tests, the most commonly used thickness and paste was chosen, this being 150-micron thick sheets and the paste was Cooksons OM338T lead free paste.The tests where done in conjunction with Cookson Electronics at their Woking laboratory using the Cookson Electronics Reliability and Functionality (CERF) Test Vehicle. During the tests some interesting results where unearthed1) It became apparent printing performance was improved once the paste and/or stencil had warmed up this was replicated by making three prints before trials commenced.2) All of the tested materials proved suitable for 02013) Of the tested stencils Datum PhD shows best overall performance, in terms of durability, wettabilrty and success rate of apertures.4) An interesting observation from the results was that the shiny (Grown side) and dull side (Mandrel side) of electroformed Nickel sheets showed differencing results, with the shiny side being far more durable and displaying preferable printing properties, when it is typically reported the dull side is the most commonly used for printing.
metal solder stencil flatness durability wettability and surface roughness.
A.C.Fischer C.H.Mahn
Datum Alloys Ltd, Unit B, Bridge Works, Station Yard Industrial Estate,Kingsbridge, UNITED KINGDOM
国际会议
Chinas Premier SMT & MPT Event(2007年中国国际表面贴装和微组装技术大会)
上海
英文
274-290
2007-03-22（万方平台首次上网日期，不代表论文的发表时间）