Wear processes in hot forging press tools

Damage Mechanisms in Salt Bath Nitro-carburised and Plasma Nitrided Hot Forging Dies of H11 Tool Steel.

“…Summerville et.al. 4) also found out cracks in the industrial hot forging dies due to alternate thermal cycles. In nitrocarburised intermediate die, horizontal thermal cracks could be observed even inside the scored regions (Fig.…”

“…The damage mechanisms responsible for reduction in life of the die may include a tribo-system specific complex combination of wear, thermal fatigue, mechanical fatigue and plastic deformation. Wear and life of forging dies are studied either from industrial data [2][3][4] or experimentally under carefully controlled conditions designed to simulate industrial practice. [5][6][7][8] There is no consensus on the dominant wear mechanism(s) affecting the die life since it is a complex function of the characteristics of die materials, tribo-system and operating parameters.…”

Performance of Fe-based hardfacings on hot forging die: experimental, numerical and industrial studies

“…It has been estimated that the cost of hot forging dies makes up about 8-15 % of the product's cost while unexpected die damage results in an increase in product's costs by 30 % [5]. Summerville et al [6] reported that almost 10 % of the final forged product value is assigned to die wear expenses, such as re-work and replacement. According to Turk et al [7], almost 17 % of total production costs are part of forging dies, thus a significant portion of costs is related to tool degradation.…”

Caracterização do desgaste em punção de forjamento a quente em prensa horizontal automática de múltiplos estágios.

“…Por isso, é natural supor que quanto mais longa for a utilização dessas ferramentas menor será o custo do produto forjado. SUMMERVILLE et al [9] apontavam que o custo das ferramentas era de cerca de 10% do custo total do produto forjado.…”

“…Sendo 0 o zero absoluto e 1 a temperatura de fusão do material [14]. Desta forma, o forjamento a frio é realizado até 0,3 da temperatura homóloga, o forjamento a morno dá-se entre 0,3 e 0,5 e o forjamento a quente entre 0,5 e 1,0 da temperatura homologa [9,14].…”