Strengthening work hardening

Mechanical Properties. An advantage of the two corrosion-resistant alloys is that they may be strengthened considerably by cold working. MP35N alloy is iatended for use ia the work-hardened or work-hardened and aged condition, and the manufacturers have suppHed considerable data concerning the mechanical properties of the alloy at different levels of cold work. Some of these data are given ia Table 8. 

The result is work-hardening the steeply rising stress-strain curve after yield, shown in Chapter 8. All metals and ceramics work-harden. It can be a nuisance if you want to roll thin sheet, work-hardening quickly raises the yield strength so much that you have to stop and anneal the metal (heat it up to remove the accumulated dislocations) before you can go on. But it is also useful it is a potent strengthening method, which can be added to the other methods to produce strong materials. 

Strong materials either have a high intrinsic strength, /, (like diamond), or they rely on the superposition of. solid solution strengthening obstacles fo and work-hardening f i, (like high-tensile steels). But before we can use this information, one problem... 

The three principle methods of strengthening materials are grain-size reduction, solid-solution strengthening, and plastic-deformation processes, like strain (work) hardening. 

Work hardening can also be used to treat material. Prior work hardening (cold working) causes the treated material to have an apparently higher yield stress. Therefore, the metal is strengthened. 

A few ceramics are ductile at RT, but the majority, under common conditions, is ductile only at some elevated temperatures. As such, temperature is a critical factor in making ceramics ductile. When discussing strengthening, in general, and work hardening, in particular, this factor will not be specifically considered unless there are extenuating circumstances. 

Non-precipitation-hardenable alloys which can be strengthened by work-hardening only. 

Steels are strengthened by a particular mechanism that is discussed in this section. This mechanism frequently is called hardening without further specification, in contrast to e. g., work hardening. 

Surveying the strengthening mechanisms discussed in chapter 6, we see that grain boundary strengthening is not suitable in creep applications because we need large grains as explained above. Work hardening can also not... 

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