铸造之星FT-STAR 科研项目简介

---

项目负责人：柳百成 院士 (Project Leader: Liu Baicheng Academician)
所在单位：清华大学 (Organization: Tsinghua University)
起止年月：1993年-1996年 (Duration of the Project: 1993-1996)

项目简介：(Project Introduction:)

用实验研究及数值模拟计算相结合的方法研究铸件缩孔缩松形成规律及定量预测缩孔缩松方法；用流场及温度场分析方法研究铸件充型过程；建立铸件三维充型凝固过程模拟分析系统。
Study on the mechanism and the quantitative prediction method of the shrinkage and porosity defects of castings by means of a combined approach of
experimental invesitgation and numerical simulation. Study on the mold filling and solidification processes of castings by numerical analysis method for the
temperature field and the flow field of castings. Establish a 3-D modeling and simulation system for the mold filling and solidification of castings.

主要研究进展及创新点：(Research Progress:)
1. 改进了铸钢件定量预测缩孔方法，提出并建立了多热节定量预测铸钢件缩孔新方法。提出并建立了定量预测球墨铸铁缩孔新方法 ，即动态收缩膨胀叠加法(DECAM)的数学模型。
1. The quantitative prediction method for the shrinkage cavity of steel castings was improved and a new method was developed to quantitatively predict
the shrinkage cavity of steel castings with multi hot spots. A new quantitative prediction method for the shrinkage cavity of spheroidal graphite castings,
the dynamic expansion and contraction accumulation method (DECAM), was proposed.

2. 改进了流场计算并提出一种三维自由表面处理的方法，可以进行复杂铸件充型过程三维流场及温度场分析。模拟计算方法经过多方面改进，显著地提高运算速度，已达到工程实用化程度。
2. The algorithm for the fluid flow simulation was improved and a 3D free surface treatment method was developed so that the 3D flow and temperature
fields of complicated castings can be modeled. The computation speed of the simulation system was remarkably increased after the modifications and
meets the requirements for practical applications.

3. 提出并实现有限差分/有限元方法集成的技术路线，解决了温度载荷转换关键技术，可以分析铸件的温度场、应力场及残余应力。
3. A combined FEM/FDM analysis approach was proposed and realized to simulate the temperature field, the stress field and the residual stress distribution
of castings. The key technique of the temperature load transfer form the FD model to the FE model was resolved.

4. 在实验室试验基础上，根据结晶及相变动力学理论，建立了凝固冷却过程各阶段的形核和长大动力学模型。在此基础上在国内首次开发了相应的微观组织与机械性能预测实用化软件，实现了三维微观组织及铸态机械性能的模拟分析。
4. Based on the experimental investigation, mathematical models for the nucleation and crystal growth were developed according to the nucleation and
phase transformation dynamics. Accordingly, the first domestic software was developed to simulate the microstructure development and to predict the as-cast
mechanical properties of castings.

5. 建立了并行工程环境下铸造CAD/CAE集成系统，并在实际工程中得到应用。可实现设计－校核－再设计的全过程。
5. A casting CAD/CAE system under the concurrent engineering environment was established and put into practical applications. The system can realize
the whole processes of design-check-redesign.

获奖情况：(Awards:)
1. "铸件充型凝固过程数值模拟研究"项目1998年获教育部科技进步(基础类)一等奖。
1. "Study on numerical simulation of mold filling and solidification of process" project got the first class award in science and technology
advancement (fundamental research) from the ministry of education in 1998.

2. 部分研究成果在国家科委863/CIMS主题攻关项目"并行工程"中得到应用，并行工程项目获1998年教育部科技进步二等奖。
2. Part of research achievements were put into application in the "Concurrent Engineering" project in 863/CIMS area from the national
science and technology committee. The "Concurrent Engineering" project got the second award in science and technology advancement
form the ministry of education in 1998.

代表性论文：(Representative papers:)
共发表学术论文47篇，有近20篇论文被多种索引收录。其中，10篇被SCI WEB收录，8篇被EI收录，1篇被ISTP收录，2篇被INSPEC收录。另外，Chemical Abstract 收录8篇，Metal Abstracts 收录7篇。4篇论文被引用11次。代表性论文目录如下：

47 papers were published. Nearly 20 papers were indexed by various index systems, in which10 papers were indexed by SCI WEB,
8 by EI, 1 by ISTP, 2 by INSPEC, 8 by Chemical Abstract, and 7 by Metal Abstracts. 4 papers were referred 11 times.
The representative papers are listed below:

1. Liu BC, Zhao HD, Liu WY, et al. Study of microstructure simulation of spheroidal graphite cast iron. INT J CAST METAL RES 11:
(6) 471-476 1999
2. Kang JW, Chen Y, Xiong SM, et al. Numerical simulation of thermal stress and deformation of engine block iron casting. INT J CAST
METAL RES 11: (6) 501-506 1999
3. Liu BC. Progress in solidification modeling of cast iron in China. INT J CAST METAL RES 11: (5) 259-266 1999
4. Li JR, Liu BC. Study of solidification shrinkage of ductile iron in dry sand molds. J MATER SCI TECHNOL 15: (3) 245-250 MAY 1999
5. Xiong Shoumei and Liu Baicheng, Study on numerical simulation of mold-filling and solidification processes of shaped casting,
Chinese J. Of Mechanical Engineering, No.1, 1999, 4-10
6. Liu BC, Qiu W, Shen HF, et al. Study and application of mold filling simulation of shaped castings. J MATER SCI TECHNOL 13:
(2) 107-112 MAR 1997

成果转化：(Technology transfer:)
部分研究成果如球墨铸铁及铸钢缩孔预测方法、流场分析、应力场分析及并行工程环境下的 铸造过程模拟等已在实际工程中得到应用，取得了显著的经济及社会效益。部分研究成果已经产业化，开发成商品化"铸造之星"软件，已在全国40多家工厂推广应用。
Part of the research achievements have been put into practical applications such as the shrinkage cavity prediction of spheroidal graphite cast iron
and steel castings, the fluid flow analysis, the stress calculation and the casting CAD/CAE system in concurrent engineering. The applications
of these achievements got remarkable economic&social benefits. By industrialization of part of the achievements, a
commercialized software named "Ft-star" was developed and has more than 40 domestic users.

联系方式：(Contact method:)
联 系 人：柳百成 院士
通信地址：北京清华大学机械工程系
邮政编码：100084
电 话：010-62773514
电子邮件：liubc@tsinghua.edu.cn

Contact person:	Liu Baicheng Academician
Postal address:	Department of Mechanical EngineeringTsinghua University Beijing
Postal code:	100084
Phone:	010-62773514
Email:	liubc@tsinghua.edu.cn

工程应用实例(Application examples)

阀体铸件充型凝固模拟(Mold filling and solidification simulation of a valve body casting)

实体造型 (Solid Model)	网格剖分 (FDM enmeshment of the casting)
充型 21.8%(21.8% filled)	充型 60.9%(60.9% filled)
充型 80.3%(80.3% filled)	初始温度场分布 (Initial temperature distribution)
凝固50分钟时温度场分布 (Temperature distribution after pouring 50 min)	缺陷X射线显示 (X-ray display for the defects)

大型铸钢件补浇工艺分析(Solidification Simulation of the Re-pouring Process for Large Steel Casting)

某大型缸体铸件,总重40吨左右，实际熔炼能力32吨左右。采用FT-STAR软件对不同层次时刻补浇工艺中铸件的凝固温度场和缩孔缩松形成情况进行了模拟，确保铸件浇铸成功。
A cylinder body casting's total weight is about 40 tons, which oversteps the factory's melting ability-about 32 tons. In order to decide the optimized re-pouring time,
different re-pouring processes were simulated by Ft-star software to predict the shrinkage cavity and porosity defects. According to all of the modeling results, a new process
was designed and used in practical production to ensure the quality of the casting.

三维实体造型 (3D solid geometry model of the casting)	网格剖分 (FDM enmeshment of the casting)
补浇前铸件凝固50分钟温度场 (Temperature distribution after pouring 50 min. before the re-pouring)	补浇前铸件凝固80分钟温度场 (Temperature distribution after pouring 80 min. before the re-pouring)
50分钟补浇时缩孔缩松预测结果 (Shrinkage/porosity prediction on vertical section if re-pouring time is 50 min)	80分钟补浇时缩孔缩松预测结果 (Shrinkage/porosity prediction on vertical section if re-pouring time is 80 min)

中空轴铸件模拟优化(Fistulous shaft casting simulation and optimization)

中空轴铸件，毛坯重1600kg。在原工艺方案条件下，废品率高达90%，回用焊补率达100%。通过凝固模拟分析，改进了原工艺方案，废品率大大降低。
A fistulous shaft casting's total weight is 1600kg. Under the primary process condition, the casting's rejection rate was as high as 90%
and 100% of the castings had to be repaired by welding. The primary process was improved by simulation and then the rejection ratio was greatly reduced.

原工艺方案 (The primary processing technology)	原工艺方案条件凝固50分钟时温度场模拟结果 (Temperature distribution after pouring 50 min. in primary process)
原工艺方案条件缩孔缩松预测结果 (Predicted Shrinkage/porosity defect in primary process)	改进工艺方案 (The improved processing technology)

球铁宏/微观模拟(Spheroidal graphite cast iron macro/micro simulation)

转向螺杆箱侧盖石墨球数量模拟结果 (Simulation result of the spheroidal graphite number of a side cover casting)	风扇支撑架硬度预测结果 (Simulation result of the hardness of a fan bracket casting)

收缩缺陷预测 (Shrinkage defect prediction)	石墨球尺寸模拟结果 (Simulation result of the spheroidal graphite dimension)
通过网络对 Ford 汽车公司球墨铸铁件进行模拟结果 (Simulation results of a spheroidal graphite casting from Ford Co. by internet)

热应力模拟(Thermal stress simulation)

700℃落砂工艺 (700℃ shake out process)	550℃落砂工艺 (550℃ shake out process)
发动机缸体铸件残余应力分析(半个缸体，沿缸体轴线方向残余应力) Residual stress analysis of an engine block casting (Half of the casting, the stress along the axis direction of casting)
残余变形(mm) Residual strain (mm)	残余应力(MPa) Residual stress (MPa)
水轮机叶片的残余应力和变形分析 (Residual strain/stress analysis of a water turbine blade casting)