The cooling applications in machining operations play a very important role and many operations cannot be carried out efficiently without cooling. Application of a coolant in a cutting process can increase tool life and dimensional accuracy, decrease cutting temperatures, surface roughness and the amount of power consumed in a metal cutting process and thus improve the productivity. In this review, liquid nitrogen, as a cryogenic coolant, was investigated in detail in terms of application methods in material removal operations and its effects on cutting tool and workpiece material properties, cutting temperature, tool wear/life, surface roughness and dimensional deviation, friction and cutting forces. As a result, cryogenic cooling has been determined as one of the most favourable method for material cutting operations due to being capable of considerable improvement in tool life and surface finish through reduction in tool wear through control of machining temperature desirably at the cutting zone.

A review of cryogenic cooling in machining processes

Determining the influence of cutting fluids on tool wear and surface roughness during turning of AISI 304 austenitic stainless steel

Astonishingly 3D printing has excited the world of aerospace. This paper takes stock of the popular 3D printing processes in aerospace. Reasons for their popularity over the traditional manufacturing processes are dwelled upon. Materials developed specially for aerospace applications along with their characteristics are discussed. Ongoing activities related to 3D printing at various companies and organisations around the world are looked into. Project works in the area of extra-terrestrial printing are also highlighted. Even though 3D printing processes are operationally simple, they do have limitations in terms of the type, quality, and quantity of the materials they can handle. This paper underlines these points while discussing drawbacks of the printed components. Challenges associated with 3D printing in microgravity are also touched upon. Finally, a glimpse is taken into the future appearance of aerospace industry with 3D printing.

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3D printing in aerospace and its long-term sustainability

Material processing of hydroxyapatite and titanium alloy (HA/Ti) composite as implant materials using powder metallurgy: A review

Investment casting (IC) has benefited numerous industries as an economical means for mass producing quality near net shape metal parts with high geometric complexity and acceptable tolerances. The economic benefits of IC are limited to mass production. The high costs and long lead-time associated with the development of hard tooling for wax pattern moulding renders IC uneconomical for low-volume production. The outstanding manufacturing capabilities of rapid prototyping (RP) and rapid tooling (RT) technologies (RP&T) are exploited to provide cost-effective solutions for low-volume IC runs. RP parts substitute traditional wax patterns for IC or serve as production moulds for wax injection moulding. This paper reviews the application and potential application of state-of-the-art RP&T techniques in IC. The techniques are examined by introducing their concepts, strengths and weaknesses. Related research carried out worldwide by different organisations and academic institutions are discussed.

Rapid prototyping and tooling techniques: a review of applications for rapid investment casting

Introduction. PART I: MATERIAL PROPERTIES AND PRODUCT ATTRIBUTES.The Nature of Materials. Mechanical Properties of Materials. Physical Properties of Materials. Dimensions, Tolerances, and Surfaces. PART II: ENGINEERING MATERIALS. Metals. Ceramics. Polymers.Composite Materials. PART III: SOLIDIFICATION PROCESSES. Fundamentals of Metal Casting. Metal Casting Processes. Glassworking. Shaping Processes for Plastics. Rubber Processing Technology. Shaping Processes for Polymer Matrix Composites. PART IV: PARTICULATE PROCESSING OF METALS AND CERAMICS. Powder Metallurgy. Processing of Ceramics and Cermets.PART V: METAL FORMING AND SHEET METALWORKING. Fundamentals of Metal Forming. Bulk Deformation Processes in Metal Working.Sheet Metal Working. PART VI: MATERIAL REMOVAL PROCESSES. Theory of Metal Machining.Machining Operations and Machine Tools. Cutting Tool Technology. Economic and Product Design Considerations in Machining. Grinding and Other Abrasive Processes. Nontraditional Machining and Thermal Cutting Processes. PART VII: PROPERTY ENHANCING AND SURFACE PROCESSING OPERATIONS. Heat Treatment of Metals. Cleaning and Surface Treatments. Coating and Deposition Processes. PART VIII: JOINING AND ASSEMBLY PROCESSES. Fundamentals of Welding.Welding Processes. Brazing, Soldering,and Adhesive Bonding. Mechanical Assembly. PART IX: SPECIAL PROCESSING AND ASSEMBLY TECHNOLOGIES.Rapid Prototypiing. Processing of Integrated Circuits. Electronics Assembly and Packaging. Microfabrication Technologies. PART X: MANUFACTURING SYSTEMS. Numerical Control and Industrial Robotics. Group Technology and Flexible Manaufacturing Systems. Production Lines. PART XI: MANUFACTURING SUPPORT SYSTEMS. Manufacturing Engineering. Production Planning and Control. Quality Control. Measurement and Inspection. Index.

Mikell P. Groover

Papers

Fundamentals of modern manufacturing : materials, processes, and systems