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如何选择正确的材料成为了许多工程师在设计时碰到的共同难题。从眼花缭乱的材料中选择最适合产品的一种并不是一件容易事，因为它很多时候决定了产品设计的成败。为了确保材料选择的正确性，工程师必须遵循以下的步骤。
4 X, Q1 l1 N, Z( j$ LOne of the most common problems a design engineer faces when designing a product is how to select an appropriate material. Selecting a single material for a product from a huge variety of options is a difficult job which can be the difference between the success or failure of a design. To ensure material selection is done properly, the designer must follow the series of steps that are described below.
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, I$ q# J+ o* m( S* e第一步：定义所需的机械特性4 }+ b% y- h, D1 x K# p
STEP 1: Define Required Mechanical Properties
8 s F6 }$ l6 q" l' m5 DThere are around 22 mechanical properties that a designer should consider. To find out which mechanical properties are critical, engineering analysis must be done to identify design constraints like applied stresses, maximum weight, etc. Engineering analysis will tell the designer whether to consider ultimate tensile strength or to select yield point stresses, or if he should select a ductile or brittle material, and what minimum safety factor is required.
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After considering the design constraints, the designer should now have a smaller range of materials that offer the required mechanical properties.
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第二步：确定可用的制造流程和生产工艺- y2 e! m7 A3 d3 w; d1 m4 P$ w) b3 j
STEP 2: Identify Available Manufacturing Processes and Capability
* g$ g5 f; d" t, JThe designer should now consider the manufacturing processes that are available. It is not uncommon for manufacturers to have lots of trouble producing a part because the designer didn’t think enough about the manufacturing process. For example, if you have selected Inconel, but cannot find manufacturer who is able to machine it satisfactorily, perhaps you should consider a more machinable material like stainless steel instead.
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第三步：审查所需的机械特性
! b; J& N2 j9 VSTEP 3: Review Required Manufacturing Properties7 C2 W8 _' E; _( V
After narrowing down your list to materials that can be processed, the designer should now review the manufacturing properties of each material. This can include castability, machineability, weldability, melting temperature and fluidity. These properties will allow you to compare which materials will raise or lower the cost to produce the part.
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9 L1 X3 Z$ v3 U第四步：确定符合条件的材料
+ s1 u! P% \9 c7 t# e* @STEP 4: Identify Available Materials
- ^# e- Y0 F2 DAfter applying the previous three filters, the designer should now have a very small list of materials, all of which have the required properties. Now he should filter the list for materials that are readily available. Selecting a material which is not available could result in delays to the project and extra cost for transporting it from a distant location.
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第五步：核算采购和制造成本
: u ~ p8 l X3 R9 wSTEP 5: Review Purchasing & Manufacturing Cost! ~4 E* d) g" F" X3 i7 Q; U
Now the designer knows which materials can fulfill the design requirements and are available in the local market. Now the designer should estimate the cost of the product, including material purchasing and manufacturing costs, with each material. He can then select the material that will result in the minimum total cost for the product. n$ U3 ]$ X; k* I/ Y d4 Q, Z
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发表于 2016-8-22 15:34:19
