Abstract: An exoskeletal rehabilitation device supports a hand, a lower arm portion, and an upper arm portion of a user relative to a supporting surface for rehabilitating the arm. The device has a shoulder frame that pivots about a first shoulder axis relative to a base frame fixed onto the supporting surface. An upper arm frame alongside the upper arm portion pivots on the shoulder frame about a second shoulder axis transverse to the first. A lower arm frame alongside the lower arm portion pivots on the upper arm frame about an upright elbow axis. A wrist frame supports a handle frame that receives the hand relative to the lower arm frame. The wrist frame pivots on the lower arm frame about a longitudinal axis longitudinal of the lower arm portion, while the handle frame pivots on the wrist frame about a wrist axis for flexion and extension of the hand.

Abstract: A die steel with a high thermal diffusion coefficient includes 0.30-0.40 wt. % of C, 0.05-0.10 wt. % of Si, 2.50-3.40 wt. % of Mo, 0.01-0.05 wt. % of Nb, 0.30-0.50 wt. % of Co, 0.01-0.05 wt. % of RE, the rest is Fe and unavoidable impurities, wherein in the die steel, P?0.15 wt. %, S?0.025 wt. %. A preparation method of the die steel includes steps of melting, electroslag remelting, electroslag ingot annealing, forging, spheroidizing annealing, quenching and tempering.

Abstract: A method for preparing a Bainite hot-working die, includes: 1) weighing and mixing alloy raw materials including: C: 0.50-0.60%, Si: 0.20-0.25%, Mn: 1.00-1.50%, W: 2.10-3.00%, Mo: 3.50-5.00%, V: 0.50-1.00%, Co: 0.60-1.10%, P?0.02%, rare earth (RE): 0.01-0.10%, (RE)/(S)>3.0, (RE)×(S)<0.004%, the balance being Fe and impurities; smelting, casting, annealing the alloy raw materials, to yield steel billets; 2) forging the steel billets to obtain Bainite die billets; 3) mechanically roughening the Bainite die billets, to yield die inserts; 4) tempering the die inserts, to yield hardened Bainite die inserts through secondary strengthening of Bainite; 5) mechanically machining the hardened Bainite die inserts to yield precisely sized die inserts; 6) nitriding the precisely sized die inserts; and 7) assembling the die inserts to yield a Bainite hot-working die.