珠光体球化的分形研究

珠光体球化反映到金相上，是一种不规则图像的变化，并且具有分形的特征，可望用分形几何的方法来进行描述。以Cr-Mo钢的珠光体球化为例，用分形维数来描述珠光体球化程度；用小岛法对15CrMo钢的珠光体球化图谱进行了测量。实验表明，珠光体球化从1级到6级，其相应的分形维数范围为1.3156-1.9282。从电厂运行了10^5h的15CrMo钢管上取样，实测了该试样的珠光体球化等级，结果表明，以分形维数表示的球化程度与按图谱评定的球化等级完全吻合。     

基体组织对蠕墨铸铁热疲劳性能的影响

主要研究了基体组织对蠕墨铸铁抗热裂性能的影响，为高速列车制动盘的合理选材提供依据。试验结果表明：铁素体基体蠕墨铸铁的耐热疲劳性能优于珠光体基体蠕墨铸铁。     

车轮断裂韧性与组织和性能的关系

研究了车轮断裂韧性与组织性能的关系。结果表明，所分析的三个车轮中(分别编为D1，D2和E1)，D1和D2车轮的KQ值分别比E1车轮的KQ值高30．0％和低14．5％。裂纹尖端延伸区宽度和铁素体百分含量与KQ值之间存在正相关关系，铬、Ceq和晶粒尺寸与KQ值之间存在负相关关系，珠光体片间距约为0．6μm时断裂韧性最高。     

珍珠岩尾砂制备4A分子筛及性能研究

将珍珠岩尾砂与氢氧化钠混合焙烧,焙烧料溶解后用水热合成法制备了4A分子筛。研究了焙烧及合成因素对产品性能的影响,制备的产品性能达到了国家分子筛用质量标准。为珍珠岩的综合利用开辟了新途径,为4A分子筛的制备提供了一种廉价原料。     

模具流道环流协同LDPE/HDPE吹塑薄膜结构性能研究

通过新型的旋转芯棒薄膜吹塑设备制备了低密度聚乙烯(LDPE)/高密度聚乙烯(HDPE)复合薄膜,并研究了该设备模具流道环流协同作用对吹塑聚乙烯薄膜结构和性能的影响。结果表明,制备的聚乙烯薄膜呈现一种互锁片晶结构;芯棒转速的提高对聚乙烯薄膜样品的结晶度、片晶厚度也有一定增益作用,使得结晶更完善;聚乙烯薄膜的拉伸性能和撕裂性能随芯棒转速提高都有所提升,尤其是横向力学性能,横向拉伸性能最大提升幅度为25.75%,横向撕裂性能最大提升幅度为27.64%;同时,该技术实现了在不影响聚乙烯薄膜的纵向热收缩率的情况下,大幅提高其横向热收缩率,提升幅度可达128.41%。     

Three-dimensional periodic Voronoi grain models and micromechanical FE-simulations of a two-phase steel

A three-dimensional model is proposed for modeling of microstructures. The model is based on the finite element method with periodic boundary conditions. The Voronoi algorithm is used to generate the geometrical model, which has a periodic grain structure that follows the original boundaries of the Voronoi cells. As an application, the model is used to model a two-phase ferrite/pearlite steel. It is shown that periodic cells with only five grains generate representative stress–strain curves.     

一起喷砂事故原因分析及防范措施

由于冷箱内低温液体泄漏,KDONAr-3500Y/1000Y/135Y型液体空分设备需要扒砂检修。但由于加温不彻底以及违规扒砂,发生了严重的爆炸性喷砂事故。介绍喷砂事故经过和破坏情况,分析喷砂原因和预防措施。     

用硬度HRC鉴别高珠光体含量球铁凸轮轴中球化率和珠光体含量的试探

通过统计分析研究了高珠光体含量球铁的基体硬度HRC与球化率(n)/珠光体含量(P)的关系.结果表明,n和P都与基体硬度HRC正相关.P＞75%～80%,HRC≤23; P＞80%～85%,HRC≤25;P＞85%～90%,HRC＞25.利用上述关系,可以用HRC对球铁凸轮轴中的球化率和珠光体含量进行鉴别.该方法已经用于生产实践.     

Texture homogeneity and stability in severely warm-rolled and annealed ultrafine pearlite

The evolution of microstructure and texture was investigated in a severely warm-rolled ultrafine pearlitic steel. The steel was 95% warm-rolled at 600°C and annealed at 700°C for different time intervals. The spheroidisation of cementite initiated after 30% reduction and completed beyond 70% reduction. The 95% warm-rolled steel showed elongated as well as ultrafine equiaxed ferrite grains. Texture inhomogeneities were evidenced by the presence of Goss component ({011} <100>) on the surface originating due to surface shear and diffuse texture at the interior. Formation of equiaxed microstructure after annealing through continuous recrystallisation resulted in the retention of the surface Goss component. However, the Goss component was destroyed beyond annealing for 180?minutes due to the abnormal growth of other grains.