Question

Give the following as functions of slug temperature: a. The strain in the slug when d 0.25 inch? (10 pts) b. The strain rate in the slug when d-0.25 inch? (10 pts) c. The flow stress in the slug when d 0.25 inch? (10 pts) d. The pressure in the matrix when d = 0.25 inch? (10 pts) Calculate (algebraically): e. The slug temperature required to keep the force applied by the ram below press capacity? Justify that your force is the maximum expected force during the deformation. (10 pts) 4. (50 pts) A cylindrical slug of initial height - I inch, and initial diameter - 1 inch is surrounded by a compressible matrix of diameter 2 inches, as shown below. The ram compresses the slug an amount to a final height of 0.75 inches (d 0.25 inches) at a speed V -5 The slug obeys the Johnson-Cook model of flow stress: po where Ơeq True flow stress tp true strain applied to slug ep true strain rate applied to slug T-T mei room and Troon = ambient temperature = 75°F T slug temperature Tmelt = slug melting temperature = 1000°F A 0 psi, B-15,000 psi, n 0.4,C 1, ep 0.001/s, and m 0.2. The pressure in the matrix is given by pei AV Pm -40,000pst omi where AV is the change in volume of the compressible matrix, and Vom is the original volume of the compressible matrix.

Answer 1

solution:-

we have to find a) strain in the slug

b) strain rate in the slug

c)true flow stress of the slug

d)pressure in the slug

ven data, Alo pe to tinal height 0.75 inc. dlhamler d 0.2s inclus ley () nain in 0.2s Ep- o.25 natn 5 Scanned with CamScanner Cs

ven, We have A n= o.4 Ep。.: 0.001 Sec- In (1+0,25) -In 11.25) Ep 0.223 (9219.9) (C,4) 52666 31' Psi = Scanned with CamScanner CS

dl tu in the Slug o. 2s = 210665·24Shi