The layer removal, progressive turning or boring, trepanning, chemical etch, modified layer removal and hole-drilling methods all rely on basically the same principle. The component is either machined, etched or drilled in stages so that the residual stresses are released producing relaxation deformations or strains which can be measured by mechanical methods or electrical resistance strain gauges and, after certain corrections, related to the initial residual stresses. Apart from the hole-drilling technique which is discussed in detail below, the other techniques of metal removal type are classed as destructive since the component cannot generally be used after the measurement procedure has been completed.
(Hearn, E., J., Mechanics of Materials: The Mechanics of Elastic and Plastic Deformation of Solids and Structural Materials, 3rd Ed., p.403)
Tube Splitting Method (March 19, 17:43):
Tube splitting is a problem involving plastic bending/stretching and tearing. When tubes axially split, they are efficient in absorbing energy and sustaining long stroke (up to 90% of tube length). In this arrangement, a tube sits on a die while compressed at the top with a plate. A curl stopper plate may be used to prevent curl formation and to enhance the axial force.
(Zhang, L., Engineering Plasticity and Impact Dynamics, p. 61)
Axiomatic Design (March 22, 12:25):
Axiomatic design is a method for guiding the efficient creation of new products, processes, systems, software, organizations, methods, etc. to obtain uncoupled or decoupled designs. According to axiomatic design, all designs involve the continuous processing of information between and within four distinct domains: consumer domain, functional domain, physical domain and process domain.
(Culley, S., Duffy, A., McMahon, C., Wallace, K., Design Methods for Performance and Sustainability, 13th International Conference on Engineering Design, p. 446)
External Failure Cost (March 22, 16:25 ):
External failure costs are one component of the cost of quality, and are incurred if a defective product reaches the customer and fails during use. The most common components of this cost are warranty work and returns. However, lawsuits from customers may also be a component. Some individuals also believe that a measure of the cost of lost goodwill should be included as a component of external failure cost. In truth, it may be difficult to accurantly estimate the real cost of external failures.
(Swamidass, P. M., Encyclopedia of Production and Manufacturing Management, p. 133)
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