Failure Analysis-Q8

Visual observation, optical microscope and scanning electron microscope are three (3) major tools that play an important role in determining the success of a root-caused analysis. Explain the each their roles in determining the (a) ductile and (b) brittle failure

[Pemerhatian mata kasar, mikroskop optik dan mikroskop elektron imbasan adalah tiga (3) alat utama yang memainkan peranan penting dalam menentukan kejayaan analisis punca-penyebab. Terangkan peranan setiap alat tersebut dalam patahan mulur dan rapuh]


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Ductile Fracture	Brittle Fracture
Visual Observation - Necking or plastic deformation - Dull and fibrous fracture surface - Shear lips	Visual Observation - Little/no plastic deformation - Shiny, course, crystalline fracture surface - Chevrons
Optical Microscopic - Plastic distortion of grains - Irregular trans-granular fracture	Optical Microscopic - Minimal deformation - Inter-granular or trans-granular
SEM Microscopic - Micro-voids elongation in direction of load - Singular crack with limited/no branching	SEM Microscopic - Cleavage or inter-granular - Discontinuity or stress riser at origin