Question

recrystallization? During grain growth? o How is the material strength affected during r o What happens on a microstructural level during cold vw ecte amncrusuecire during recovery? During ecovery? During recrystallization? During grain growth? As you read through the sections of Ch. 8, consider the following questions: o What are the similarities & differences between ductile and brittle fracture? o What are the similarities & differences between transgranular and intergranular fracture? o How do cracks cause materials to be weaker than their theoretical strength? o What is a stress intensity factor? And how is it affected by crack length, crack tip radius of curvature, and other geometric factors? what is fracture toughness, and how is that related to the stress intensity factor? o How is specific surface energy related to crack propagation in a brittle material?

Answer 1

Question: What are the Similarities L di#erences between » duclile an bittle fracre Depending on the abity ef material to undee plastie defovmalion before the Avacture, tuso frackue mades can be defined ducble or biue Ductile fracture:-Extensive plastic defoǐmation and energy absospbo (toughness) befre failure . -) cxac k ß stable . Yesists futhex cxtensen uness applied śbess Ls incieased → most Metals (rcttco(old) e duchie - Soft metals at soon beneaue, Polymers Oghses at hih tempefatufe 9→ Moderately ducble ._ typicd foç duckie met Neck OcCurs at the time of failure → Formation of microvoids → coalescence of micro Voids to frm a cack BritHe kacure litHe pasbc defomalion and lous energy absorpti before failurc cack fs unstable prepagates apiy uthout inctea-5o in applied Stress cack propagalion is vesy fast → CYack propagates nearly perpendicular the direction of the oppied Stress CYack often propagakes by Cleavaje -breaking ot atomic o bonds along Speuifc cystallegaphic planes.

DUcile strain

Questienwhat ave the Similasities 4 difevences bctween transgianu lay and inbesanula raclure ? Fracture Surface have faceled texbure because of dievent oxien tation ot cleavaqe planes in gains Inbergeoula acture Fxaeture Crack propajabien is along grain boundaries Cgrain boundaries are weakened or embYttled by impunties Scgrejabon ete)
QUESTION 3:

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