Review Materials Enabled Designs: The Materials Engineering Perspective to Product Design and Manufacturing

Most of electronics assembly is achieved in non-mechanical bonding processes: lamination, plating, soldering, underfill, encapsulation, and so on. Even mechanical joining — such as board-to-board connectors — is based in one or more material-based interconnect. I promised a review of a materials-focused text in the blog post, New Materials for an Evolving Industry, and Michael Pfeifer's text delivers the well-rounded, prototype-to-production viewpoint of materials usage we were looking for.

Pfeifer’s new text book, Materials Enabled Designs: The Materials Engineering Perspective to Product Design and Manufacturing, published by Butterworth-Heinemann, an imprint of Elsevier, covers design, materials, manufacturing processes, reliability, quality and process control, yield, and cost management with materials as the focus. Engineers should “better understand the risks and rewards associated with…materials used in a product; the manufacturing processes used to produce the product; and the suppliers of materials, components, and subassemblies used in a product,” Pfeifer asserts.

The book also has sections focused on total product design practices and smart operating procedures, which requires most companies to specify components without strict controls over all materials used. Pfeifer offers these tips:
“Start with materials that offer a high probability of success. Do not consider the entire world of materials, components, and subassemblies for use in a product. Work out all details of a strategic custom component or subassembly before using a low-cost supplier. Consolidate materials within and across product platforms. Develop design guidelines. Include a budget for materials engineering support.”

Flow charts and matrices throughout the chapters are visual prompts to readers, asking them to consider product design with discipline and constructive creativity.

While a large portion of the text is devoted to material properties and materials science, the theme throughout is about perspective. The reader should emerge with a stronger background in properties of solders, surface finishes, etc., and — more importantly — with a concept of the role materials play in a product’s success, from design to sourcing to manufacturing and test. As Pfeifer states, poor understanding of materials science can lead to “delayed product launch, field failures, poor customer satisfaction, and poor sales.” He encourages “understanding the relationship between the properties of a material, its compositions, its microscopic structures, and how it was processed.” For example, a high-volume assembly may be dense and small with high computing power, but if the solder specified is easily degraded by the print process, frequent downtime at the printer will kill expected yields. Materials ignorance can be costly.

The text is available from Elsevier. Pfeifer is president of Industrial Metallurgists LLC. He wrote the book based on materials compiled for a Manufacturing and Design Engineering (MaDE) program course at Northwestern University.

Meredith Courtemanche, managing editor

New Materials for an Evolving Industry

Materials innovations are helping to reshape our industry in the post-RoHS, halogen-free era. Environmental constraints, usability requirements, cleaning issues, and other factors are bearing down on solders, conformal coatings, underfills, and all the other “goo” that helps construct and protect an assembly. Check out this week’s soldering products roundup to see some of these innovative chemistries. At APEX 2009, I sat down with Doug Dixon, global marketing manager, at the electronics group of Henkel, to discuss materials trends in the industry, and how suppliers are shouldering the burden.

Henkel has been busy since last year’s acquisition of Emerson & Cuming and Ablestik. Now that the majority of integration tasks calendared in since last year’s APEX have occurred, this year’s event found the company releasing new materials resulting from these collaborations. Henkel had two products in the show’s Innovative Technology Center: Multicore LF700 lead-free solder paste and the Hysol UF3800 underfill.

Henkel brought in the Emerson & Cuming team while developing UF3800, Dixon noted, and the collaboration proved fruitful. The product won an SMT VISION award this year. UF3800’s benefits include underfilling that flows at room temperature and cures at low temperature, halogen-free, rework-capable, high T_g, lower energy use (due to eliminating pre-heat to flow and cure), and compatibility with many flux formulations. LF700 offers a long abandon time even when printed onto 0.4-mm CSP apertures, reduced voiding in BGA solder joints (due to the flux chemistry), humidity resistance, and high tack force. Its halide- and lead-free ingredients label should also encourage global use regardless of regional environmental restrictions, such as RoHS, China RoHS, and other state-by-state directives.

Both the paste and underfill satisfy externally imposed requirements — lead- and halide-free. They also meet internal manufacturing requirements — reworkability, fine-pitch printing, broad flux compatibility — to ease the manufacturing and reporting burden on electronics makers. Dixon said these “hybrid chemistries” are advancements marked on the company’s product roadmap.

Acquisitions may seem like a dangerous move in a tight economy, but Henkel’s method of adding units that complement existing product groups is sound: Some products may overlap, but the overall trend is expanding in an application area — not stacking similar products on top of one another. “We go through all our projects and combine resources where it will make a positive impact,” Dixon said. Some projects have natural crossover, like the CSP underfill or certain die-attach products. Others, such as conductive inks, are a new area for Henkel since the National Starch acquisition.

Emerson & Cuming has a developed base in the defense sector, so Henkel is working to combine potting/encapsulation and conformal coating IP into new products. The result is a conductive film product called CF3366, which provides RF grounding in PCB-to-housing interconnections. The high-adhesion-strength electrically conductive film is formulated for electrical, thermal and mechanical assembly applications and targets harsh environments with high temperature resistance. It enables thermal release as well as adhesion, tackling two system-level challenges.

Beyond acquisitions, Henkel’s business development group partners with universities and research groups for product development on a longer timeline. Joint ventures are another area of interest. A colleague of mine recently returned from a tradeshow with a clear message: Collaboration is king in the new economy. For project developments occurring now to 5 and 0 years down the road, the balance of collaboration and mergers & acquisitions will bring in investments from interested customers, fueling continued R&D in this cautious economic climate.

Continuing on this theme of materials evolution, SMT just received a copy of the new publication, Materials Enabled Designs: The Materials Engineering Perspective to Product Design and Manufacturing, written by Michael Pfeifer, president of Industrial Metallurgists LLC. The 12-chapter book covers product design, materials selection, materials reliability and performance considerations, costs and market ramp-up strategies, and other aspects of the process, from the materials engineer's perspective. Look for a review of the text in an upcoming blog post.

Meredith Courtemanche, managing editor