manufacturing processes 1 Flashcards
Q: What is the simplified metal cutting model assumption?
A: It assumes two-dimensional plastic deformation with no side spread of the chip and orthogonal cutting, meaning the major cutting edge is perpendicular to the tool’s motion.
Q: What is chip thickness ratio (cutting ratio, rc)?
A: The ratio between the thickness of the chip after cutting (ac) and the thickness of the undeformed layer (a0), always less than 1.
Q: How does the rake angle affect chip formation in cutting?
A: A smaller or negative rake angle increases plastic deformation, chip thickness, and cutting forces, while a larger rake angle reduces these effects.
Q: What is material removal rate (MRR) in metal cutting?
A: MRR is the volume of material removed by the cutting tool per unit time, calculated as MRR=v×a0 ×f.
Q: What is the effect of cutting temperature on tool performance?
A: Increased cutting temperatures can decrease tool hardness and strength, leading to faster wear and potential thermal deformation of both the tool and workpiece.
Q: What are the main roles of cutting fluids?
A: Cutting fluids reduce friction, cool the cutting zone, wash away chips, and protect the machined surface from corrosion.
Q: What are the different types of chips in metal cutting?
A: The major types are continuous chips, segmented chips, and discontinuous chips, which depend on cutting conditions and material properties.
Q: What are the primary types of tool wear in metal cutting?
A: The two main types are flank wear and crater wear, caused by abrasion, adhesion, diffusion, chemical reactions, and oxidation.
Q: What is tool life in cutting?
A: Tool life is the duration a tool can perform reliable cutting before it needs to be reshaped or replaced, typically determined by flank wear.
Q: What materials are used for cutting tools?
A: Common materials include high-speed steel (HSS), cemented carbides, ceramics, cermets, cubic boron nitride (CBN), and diamond.
