模具间隙对热冲压钢板BR1500HS性能影响研究(2)

菜单

High strength steel BR1500HS as experimental object in this paper, first, to develop high strength steel plate, such as mild non isothermal deformation experiment research, comparative analysis under the different temperature and different clearance effect on microstructure of the material, then the mold clearance experiment is based on three different thickness of sheet metal under the same mold clearance to achieve the effect of changes in clearance, analyzes the different gap's influence on the microstructures and properties of boron steel plate.

Results the following conclusions mild BR1500HS waiting for non isothermal deformation experiment of different microstructure. Cooling rate is within 10-20 ℃ / s, the isothermal deformation of the microstructure of martensite and bainite hybrid organization; However the non-isothermal deformation microstructure appear less martensite, the deformation in the high temperature at the end of the organization to the mixture of ferrite and pearlite.

Moreover mold clearance BR1500HS organization performance impact experiment, has carried on the parts local microstructure observation, through the comparative study of 1.0 mm, 1.4 mm and 1.6 mm analysis under the die clearance of 1.8 mm, 1.8 mm thick of boron steel plate stamping forming out of the box surface quality and parts are ideal local martensite content.

KeyWords: high strength steel plate; hot stamping; microstructure;

1绪论 1

1.1热冲压简介 1

1.2高强度钢板分类 3

1.3国内外研究现状与水平 5

1.4研究意义与目的 7

2 实验材料及方案 8

2.1 试样与仪器 8

2.1.1 实验材料 8

2.1.2 实验仪器 9

2.2 实验方案 10

2.2.1 高强钢BR1500HS的高温性能实验 10

2.2.2模具间隙实验方案 11

3 结果与分析 13

3.1 等温和非等温变形实验 13

3.2模具间隙对冲压件微观组织的影响 14

4 全文总结及展望 17

5参考文献 18

6致谢 21

1绪论

随着日新月异的科技发展以及人民消费水平的提高，汽车保有量越来越高，使用燃油用量也越来越多。所以，造成世界石油燃料等短缺、造成的环境污染越来越严重。交通工具的“轻量化车身、绿色环保节能减排”重要措施，开始被许多制造车辆厂家开始重视。研究表明最有效降低排放的措施是减轻汽车自身车重[1-2]。因此，汽车制造业发展的趋势逐渐趋向于轻量化、安全高强度。一般有三种方法使汽车车身轻量化：第一可以采用本身质量较轻的金属材料，如镁铝合金、高强钢薄板等；第二设计优化减少汽车上不必要的补强件；第三采用最新的科技研发新的制造方法。其中高强度钢板被人们所看好，具有广阔应用前景如图1.1。但是轻量化零件被投入生产使用前，需要长时间的检测、重新优化结构且都比较复杂。此外如果使用镁铝合金这一类的产品，其较高的成本，复杂的的铸造流程以及高难度的焊接工艺等问题使得这类产品在汽车领域难以有大规模运用。与之相比，高强度钢不仅弥补了之前的弊端，还在抗拉强度、加工工艺等方面有更广阔的前景。运用高强度薄钢板，提高安全性能的同时，也能明显降低汽车整体的质量，所以能广泛运用汽车制造行业[1]。