Sintering: From Empirical Observations To Scientific Principles

 

PREFACE

Exciting new designs are enabled by the sintering process. Although practiced for over  28,000 years, recent discoveries are moving sintering into some bold new applications. New energy systems, ranging from solar cells to nuclear reactors, are critically contingent on sintered structures. Another example is the fabrication of porous tissue scaffolds for  biomed bio medical ical implant implants, s, in which which the device device is custom custom laser sinter sintered ed to match match strengt strength h and elastic modulus of the patient. In the same manner, dental crown and bridge construct struction ionss are pr produ oduced ced ov overnig ernight ht using using additi additive ve comput computer er driven driven sinteri sintering ng route routes. s. An enormous effort is pushing forward the sintering of thin printed electronic structures, such as small radio frequency identification circuits to be embedded in consumer products,, allowing ducts allowing information information transfer transfer when activated by near-field near-field cellular cellular telephones. telephones. Related efforts are taking place in replacement interconnections for solar cells and a host of capacitor, energy storage, and magnet devices. The field of superabrasives is producing sinter sin tered ed diamon diamond d bonded bonded onto onto sinter sintered ed cement cemented ed carbid carbides es substr substrate atess to make make longlonglasting oil and gas drilling tools. Another growth area is that of sintered thermoelectric  junctions  junct ions to convert convert waste waste heat into electricity electricity, including including waste waste heat from automobile automobile engines. This modern era of sintering traces to the early 1800s when the first platinum crucibles were made for melting glass. Significant progress came in the early 1900s with the production of incandescent lamp filaments, but theoretical explanations awaited the development of atomic theory and the atomic motion concepts that emerged in the 1940s. Once atomic theory the ory was melded melded with sintering sintering observa observation tions, s, quantita quantitativ tivee conc conceptu eptualiza alization tionss arose. arose. In turn, that effort matured matured to produce produce compute computerr simulat simulation ions. s. Now those simulat simulations ions are approaching the accuracy that is demanded by manufacturing. Soon extraterrestrial sintering will use lunar soils and solar energy to construct buildings on the moon. The prospects for expanded applications are outstanding. This book explains the basics of sintering. The concepts are equally applicable to the fabrication fabricat ion of electro electronic nic capacito capacitors, rs, automoti automotive ve transmi transmissio ssion n gears, gears, high intensit intensity y lights, lights,  jet engine engine contro controll linkages linkages,, or high speed speed end mills. mills. The approach approach starts starts with historical historical concepts, mixes history and science, and outlines the theoretical evolution. The scientific underpinnings arose from simple questions that form the key points covered by this book: What is sintering? How do we observe sintering? What are some of the key parameters? How can we improve sintering? Where did sintering theory come from? Where do we stand on modeling sintering?

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Preface

Included are chapters on emerging topics, such as the role of rapid heating, and introductions to sintering tools. The effort of writing this book started in the preparation of a Plenary Seminar for  Sintering Sinte ring 2011   and and a Keyno eynote te Lect Lectur uree fo forr the the   2012 Materials Materials Scienc Sciencee and Technolo echnology gy Conference . My thanks go to Suk-Joong Kang, Eugene Olevsky, and Khalid Morsi for  their early support. Several students helped, notably Wei Li, Timothy Young, Michael Brook Brooks, s, and Shuang Shuang Qiao. Qiao. Kenne Kenneth th Brook Brookes es pr prov ovide ided d backgr backgroun ound d informa informatio tion n on sintered carbides, while Zak Fang, Animesh Bose, and Donald Heaney organized relevant revie reviews ws.. Loui Louiss Rect Rector or and Howa Howard rd Glic Glicks ksman man pro provide vided d inform informati ation on on sint sinter ered ed electronic applications. Lanny Pease donated a missing book to provide insights. Other  missin mis sing g informa information tion was obtain obtained ed fr from om the Metal Metal Powder owder Indus Industries tries Feder Federati ation on and American Ceramic Society. I am thankful to a host of other individuals for their efforts and kind words, and to San Diego State University for giving semesters without teaching to complete this project. This book is dedicated to Animesh Bose; he is a testimonial to what can be done by applying sintering. And the scary thing is his children are smarter and more motivated. Randall M. German