GATE Mechanical Engineering (ME) 2015 Shift 1 Solved Paper

In a slab rolling operation, the maximum thickness reduction (Δh_max) is given by Δh_max = μ²R, where R is the radius of the roll and μ is the coefficient of friction between the roll and the sheet. If μ = 0.1, the maximum angle subtended by the deformation zone at the centre of the roll (bite angle in degree) is ______.