(a) Powder metallurgy (PM) is a net-shape forming process by which fine powdered materials are blended, pressed into the desired shape (compacted), and then heated (sintered) in a controlled atmosphere to bond the contacting surfaces of the particles and establish desired properties. i) Justify the reasons why powder-metal parts are commonly used for machine elements which requiring good tribological characteristics. ii) Compaction is the step in which high pressure is applied to the powders to form them into the desired shapes. The purposes of compaction are to obtain the required shape, density, and particle-to-particle contact. In your opinion, is there any density variation in the compacting of powders? Justify your answer. If your answer is yes, propose appropriate methods to reduce the variation.

(a) Powder metallurgy (PM) is a net-shape forming process by which fine powdered materials are blended, pressed into the desired shape (compacted), and then heated (sintered) in a controlled atmosphere to bond the contacting surfaces of the particles and establish desired properties. i) Justify the reasons why powder-metal parts are commonly used for machine elements which requiring good tribological characteristics. ii) Compaction is the step in which high pressure is applied to the powders to form them into the desired shapes. The purposes of compaction are to obtain the required shape, density, and particle-to-particle contact. In your opinion, is there any density variation in the compacting of powders? Justify your answer. If your answer is yes, propose appropriate methods to reduce the variation.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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