© April 2018 | IJIRT | Volume 4 Issue 11 | ISSN: 2349-6002 IJIRT 146002 INTERNATIONAL JOURNAL OF INNOVATIVE RESEARCH IN TECHNOLOGY 1166 Design of Parts using Additive Manufacturing (AM) & Reverse Engineering (RE) – A Review Nikhil Wadatkar 1 , Ujwal Danade 2 , Dr.R.M.Metkar 3 1,2 PG Scholar, Dept. of Mechanical Engineering, Government College of Engineering Amravati, Maharastra 444604 3 Assistant Professor, Dept. of Mechanical Engineering, Government College of Engineering Amravati, Maharastra 444604 Abstract- Rapid prototyping technologies are able to produce physical model in a layer by layer manner directly from their CAD models without any tools, dies and fixtures and also with little human intervention. RP is capable to fabricate parts quickly with too complex shape easily as compared to traditional manufacturing technology. RP helps in earlier detection and reduction of design errors. Rapid prototyping has gained widespread industrial acceptance as a means of quickly and economically producing small quantities of physical objects. In addition to its commercial applications, rapid prototyping tools have the potential to drastically influence the ways people create and their reasons for doing so. Digital fabrication promises individuals means of creating complex objects with virtually no prerequisite skill. Companies in the development phase preceding mass production and the individual maker face similar issues. Before committing to producing a million copies of a design, it is imperative that small quantities of prototypes are generated and validated. Production machinery, whose operation relies upon economies of scale, is impractical for the task. Thus was born the field of rapid prototyping (RP). While the term typically evokes mental images of three-dimensional printers, the underlying spirit can be expressed simply: the automated creation of a physical object from a digital representation. INTRODUCT ION (I) Basic Principle Of Rapid Prototyping Processes RP process belong to the generative (or additive) production processes unlike subtractive or forming processes such as lathing, milling, grinding or coining etc. in which form is shaped by material removal or plastic deformation. In all commercial RP processes, the part is fabricated by deposition of layers contoured in a (x-y) plane two dimensionally. The third dimension (z) results from single layers being stacked up on top of each other, but not as a continuous z-coordinate. Therefore, the prototypes are very exact on the x-y plane but have stair- stepping effect in z-direction. If model is deposited with very fine layers, i.e., smaller z-stepping, model looks like original. RP can be classified into two fundamental process steps namely generation of mathematical layer information and generation of physical layer model. The first step in the process is creating the digital (i.e. mathematical) representation of a concept. This is accomplished using a computer software package known as a computer aided design (CAD) tool. The second step, therefore, is to convert the CAD file into STL format (Any prototyping technique format). This format represents a three- dimensional surface as an assembly of planar triangles. In the third step, a pre-processing program prepares the STL file to be built. The fourth step is the actual construction of the part. RP machines build one layer at a time from polymers, paper, or powdered metal. The final step is post-processing. This involves removing the prototype from the machine and detaching any supports. Types of RP technologies now - Stereo lithography - Fused Deposition Modelling - Laminated Object Manufacturing - Selective laser sintering (SLS) (II) Additive Manufacturing (AM) is an nearer name to describe the technologies that build 3D objects by adding layer-upon-layer of material, whether the material is plastic, metal, concrete or one day. Human tissue. Common to AM technologies is the use of a computer, 3D modeling software (Computer Aided Design or CAD), machine