Figure 9-6 9-49 An aluminum alloy plate with dimensions 20 cm x 10 cm × 2 cm needs to be cast with a secondary dendrite arm spacing of 10-2 cm (refer to Figure 9-6). What mold constant B is required (assume n = 2 )? Secondary dendrite arm spacing (cm) - 10-1 10-2 10-3 10 41 0.1 1 Copper Zinc alloys Aluminum alloys 10 100 1,000 10,000 100,000 Solidification time (s)

Figure 9-6 9-49 An aluminum alloy plate with dimensions 20 cm x 10 cm × 2 cm needs to be cast with a secondary dendrite arm spacing of 10-2 cm (refer to Figure 9-6). What mold constant B is required (assume n = 2 )? Secondary dendrite arm spacing (cm) - 10-1 10-2 10-3 10 41 0.1 1 Copper Zinc alloys Aluminum alloys 10 100 1,000 10,000 100,000 Solidification time (s)

Precision Machining Technology (MindTap Course List)

2nd Edition

ISBN:9781285444543

Author:Peter J. Hoffman, Eric S. Hopewell, Brian Janes

Publisher:Peter J. Hoffman, Eric S. Hopewell, Brian Janes

Chapter2: Measurement, Materials, And Safety

Section2.7: Heat Treatment Of Metals

Problem 2RQ: Direct hardening can be performed on steel containing at least________ carbon.

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For each question, provide an explanation, identifying the correct choice ( it is marked in red) and explaining why it's the right answer, as well as why the other options are incorrect.