Tham khảo tài liệu 'metal fatigue part 8', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 194 Chapter 10 Table Cast numbers and chemical composition Analysis wt. Cast No Mean size of particles added c Si Mn s p Ni Cr Mo im Commercial En24 cast JK None Laboratory En24 cast 1 None Laboratory En24 casts with angular alumina particles added 55 73 56 65 61 65 63 40 78 30 76 20 77 10 84 73 119 63 118 45 117 28 116 19 115 9 Laboratory En24 casts with spherical alumina particles S11 73 added S2 63 S4 45 S7 34 S6 20 S8 10 Table shows the cast number the nominal size of the added alumina particles and the results of chemical analysis of the ingots. Particles of two shapes were added angular and spherical. Angular particles were added to casts numbers 55 56 61 63 76-78 84 and 115-119 and spherical particles to casts numbers S2 S4 S6-S8 and Sil. All ingots were forged and rolled to a diameter bar. All test piece blanks were annealed before machining by heating at 650 C for 4 h. They were then rough machined to mm oversize in all dimensions. Subsequent heat treatment was heating at 850 C for 1 h followed by oil quenching and tempering at 200 C for 8 h. The hardness of each .
