PSI - Issue 33

Muhammad Faiz Dzulfiqar et al. / Procedia Structural Integrity 33 (2021) 59–66 Dzulfiqar et al. / Structural Integrity Procedia 00 (2019) 000–000

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1. Introduction There are numerous mechanical design objectives that are safe, reliable, efficient, economical, and practical to manufacture (Mott., 2018). In an era of rapidly emerging product innovations, quality control is one of the critical processes in engineering (Caesar et al., 2020a;b). Hence, manufacturers are facing a challenge to improve production performance to sustain their competitive advantages and maximizing profit. There are three main fundamental functions, production control, maintenance scheduling, and quality control which have significant impacts on production performance (Cheng et al., 2018). Most of the industry has shifted from manual tools to automatic machines, so do the thickness checker. One of the first applications of ultrasonic resonance to make thickness measurements provided the acoustic properties of the membrane are known (Lerch., 2021). Thickness measurement has an essential role in brake pad manufacturers. An example of thickness measurement in the industry, e.g., Akebono Brake Astra Indonesia Quality Control's Department that use the ultrasonic thickness gauge operated by a man to check the specimen one by one. Nomenclature � Maximum principal stress in a bi-axial stress system � Minimum principal stress in a bi-axial stress system � Normal stress Factor of safety Density Bending moment Distance of the section from the left and of the beam Modulus elasticity The moment of inertia of the cross-section about its neutral axis � , � Constant of integration

2. Literature Review 2.1. Von-Mises stress

The von-Mises criterion is also known as the maximum distortion energy criterion (Wang et al., 2021). This criterion concludes that failure or yielding on a given structural component when the value of the distortion strain energy (also called shear strain energy) per unit volume in that material reaches the limiting distortion energy per unit volume required to cause yield as determined from a simple tension test (Khurmi and Gupta, 2005). The maximum distortion energy for yielding is given by Equation 1.

2

2

2

a b y         a b

(1)

Introducing a factor of safety into Equation 2.

2

2          . F S  y

2     a b b a

(2)

2.2. Factor of safety In order for a machine component can perform safely, the maximum load carried out by the machine component under normal conditions is considerably smaller than the ultimate load (Beer., 2013). Under this circumstance, the