Designed materials
Encyclopedia
Designed materials
Designed materials
Designed materials or Smart material is a material whose structure and composition has been deliberately manipulated to affect the material’s properties in a controlled fashion to achieve a specific functionality unexpected or significantly different from the original material.Quest for a material...

 or Smart material
Smart material
Smart materials or designed materials are materials that have one or more properties that can be significantly changed in a controlled fashion by external stimuli, such as stress, temperature, moisture, pH, electric or magnetic fields....

 
is a material
Material
Material is anything made of matter, constituted of one or more substances. Wood, cement, hydrogen, air and water are all examples of materials. Sometimes the term "material" is used more narrowly to refer to substances or components with certain physical properties that are used as inputs to...

 whose structure and composition has been deliberately manipulated to affect the material’s properties in a controlled fashion to achieve a specific functionality unexpected or significantly different from the original material.


Quest for a material to suit the service performance is almost as old as human civilization. So far materials engineers have developed a series of alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...

s, polymer
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

s, ceramic
Ceramic
A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous...

s, and composite
Composite material
Composite materials, often shortened to composites or called composition materials, are engineered or naturally occurring materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or...

s to serve many of the performance requirements in a modern society. However, challenges appear when one needs to satisfy more than one boundary condition. For example, a component with negative Coefficient of Thermal Expansion (CTE) using a ductile metal was almost impossible until recently. Synthesis of various technologies such as Direct Metal/Material Deposition (DMD) Homogenization Design Method (HDM) and multi material Computer Aided Design
Computer-aided design
Computer-aided design , also known as computer-aided design and drafting , is the use of computer technology for the process of design and design-documentation. Computer Aided Drafting describes the process of drafting with a computer...

 (CAD) was necessary to achieve this goal. Rapid fabrication of three-dimensional shapes of engineering materials such as H13 tool steel
Tool steel
Tool steel refers to a variety of carbon and alloy steels that are particularly well-suited to be made into tools. Their suitability comes from their distinctive hardness, resistance to abrasion, their ability to hold a cutting edge, and/or their resistance to deformation at elevated temperatures...

 and nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

 super alloys are now possible using Direct Materials Deposition (DMD) technique as well as similar techniques such as Light Engineered New Shaping (LENS) or Directed Light Fabrication (DLF). However, DMD has closed loop
Closed loop
Closed loop may refer to:* A feedback loop, often found in:** Control theory#Closed-loop transfer function, where a closed-loop controller may be used** Electronic feedback loops in electronic circuits** PID controller, a commonly used closed-loop controller...

 capability that enables better dimension and thermal cycle control. This enables one to deposit different material at different pixels with a given height directly from a CAD drawing. The feedback loop also controls the thermal cycle. H13 tool steel is one of the difficult alloys for deposition due to residual stress accumulation from martensitic transformation. However, it is the material of choice for the die and tool industry. DMD has demonstrated successful fabrication of complicated shapes and dies and tools, even with H13 alloys. This process also offers copper chill blocks and water-cooling channels as the integral part of the tool
Tool
A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

. On the other hand ZrO2 was co-deposited with nickel super alloys using DMD. Flexibility of the process is enormous and essentially it is an enabling technology to marterialize many a design. Using DMD in conjunction with HDM and multi-material CAD, one can produce components with predetermined performance such as negative co-efficient of expansion, by synthesis of designed microstructure.

Reference

1. Designed materials: what and how? First International Symposium on High-Power Laser Macroprocessing, Isamu Miyamoto; Kojiro F. Kobayashi; Koji Sugioka; Reinhart Poprawe; Henry Helvajian, Editors, pp. 505–516


2. http://www.vinnova.se/en/Activities/Designed-Materials/
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