二战后世界经济格局的演变世界经济格局，是指活跃于世界经济领域并充当主角的国家和国际经济组织之间在一定历史时期内相互作用形成的一种结构、态势。
其核心内容是大国或国家集团之间的经济力量对比关系和支配世界经济的权力分配状况。
世界经济格局的变化，取决于各个国家或国家集团经济实力的彼此消长。
在二战至今不到六十年的时间里，世界经济格局却发生了三次重大演变:战后初期到60年代末的美国称霸世界经济领域;70年代后世界经济向多极化方向发展;80年代末以来世界三大区域经济集团化加快发展。
总之，在战后短短的50多年中，世界经济格局经历了从一极到多极的演变过程。
每一次演变都给世界产生了巨大的影响。
一、第一次:美国成为资本主义世界经济霸主(战后初期至70年代)1原因: 战使西欧各国遭到严重削弱，美国远离战场，没有受到战争的破坏，在战争中通过贷款、出卖武器、后勤物资等，获取了大量财富。
战后，美国大力拓展世界市场，应用最新科学技术成果，革新生产技术，发展新兴工业，促进了经济的稳定发展。
美国资产阶级还向世界各地输出资本，扩大海外市场，赚取高额利润。
2表现: 美国拥有最雄厚的工业实力，到50年代中期，全世界一半以上的商品是美国生产的。
黄金储备也最丰富。
在战后传统的以英镑为中心的资本主义世界货币体系难以维持的情况下，美国将美元appearance of the weld appearance quality technical requirements of the project must not have a molten metal stream does not melt the base metal to weld, weld seam and heat-affected zone surface must not have cracks, pores, defects such as crater and ash, surface smoothing, weld and base metal should be evenlysmooth transition. Width 2-3 mm from the edge of weld Groove. Surface reinforcement should be less than or equal to 1 + 0.2 times the slope edge width, and should not be greater than 4 mm. Depth of undercut should be less than or equal to 0.5 mm, total length of the welds on both sides undercut not exceed 10% of the weld length, and long continuous should not be greater than 100 mm. Wrong side should be less than or at 0.2T, and should not be greater than 2 mm (wall thickness mm t) incomplete or not allow 7.5 7.5.1 installation quality process standards of the electrical enclosure Cabinet surface is clean, neat, no significant phenomenon of convex, close to nature, close the door. 7.5.2 Cabinet Cabinet face paints no paint, returned to rusted, consistent color. 7.5.3 uniform indirect gap from top to bottom, slot width <1.5mm 7.5.4 adjacent Cabinet surface roughness is 0. 7.5.5 the cabinets firmly fixed, crafts beautiful. 7.5.6 Cabinet surface gauge, switch cabinet mark clear, neat, firm paste. 7.5.7 Terminal row of neat, is reliable, the appearance is clean and not damaged. 7.5.8 cables neat and clean, solid binding, binding process in appearance. 7.5.9 the first cable production firm, crafts beautiful, clear signage does not fade. 7.5.10 fireproof plugging tight, no cracks and pores. 7.6 7.6.1 of the standard electrical wiring quality technology cable a, the multi-core wire bunch arrangement should be parallel to each other, horizontal wire harness or wire should be perpendicular to the longitudinal multi-core wire bunch. The distance between the wire harness and wire harness symmetry, and asclose as possible. B-core wiring harness into round, multi-core wire bunch used g wire binding, fastening与黄金挂钩，其他资本主义国家货币与美元挂钩，建立了以美元为中心的资本主义世界货币制度——“布雷顿森林体系”。
