Theoretical modeling of cutting temperature in high-speed end milling process for die/mold machining

A parametric model of cutting temperature generated in end milling process is developed according to the thermal mechanism of end milling as an intermittent operation, which periodically repeats the cycle of heating under cutting and cooling under non-cutting. It shows that cutting speed and the tool-workpiece engagement condition are determinative for tool temperature in the operation. The suggested model was investigated by tests of AlTiN coated endmill machining hardened die steel JIS SKD61, where cutting temperature on the flank face of tool was measured with an optical fiber type radiation thermometer. Experimental results show that the tendency of cutting temperature to increase with cutting speed and engagement angle is intensified with the progressing tool wear.

Low-cycle fatigue behavior of permanent mold cast and die-cast Al-Si-Cu-Mg alloys

Fatigue failure is one of the main failure forms of Al-Si-Cu-Mg aluminum alloys. To feature their mechanical aspect of fatigue behavior, the low-cycle fatigue behavior of permanent mold cast and die-cast AI-Si- Cu-Mg alloys at room temperature was investigated. The experimental results show that both permanent mold cast and die-cast AI-Si-Cu-Mg alloys mainly exhibit cyclic strain hardening. At the same total strain amplitude, the diecast AI-Si-Cu-Mg alloy shows higher cyclic deformation resistance and longer fatigue life than does the permanent mold cast AI-Si-Cu-Mg alloy. The relationship between both elastic and plastic strain amplitudes with reversals to failure shows a monotonic linear behavior, and can be described by the Basquin and Coffin-Manson equations, respectively.

Optimization strategy in end milling process for high speed machining of hardened die/mold steel

An optimization strategy for high speed machining of hardened die/mold steel based on machining feature analysis was studied. It is a further extension of the previously presented study on the thermal mechanism of end milling and constant cutting force control. An objective function concerning machining cost and associated optimization algorithm based on machining time and cutting length calculation was proposed. Constraints to satisfy specific machining strategies when high speed machining the hardened die/mold steel, trochoid tool path pattern in slot end milling to avoid over-heat and feed rate adaptation to avoid over-load, were also discussed. As a case study, the tool selection problem when machining a die part with multiple machining features was investigated.

HSM strategy study for hardened die and mold steels manufacturing based on the mechanical and thermal load reduction strategy

The paper discussed cutter-work engagement situation hidden behind the mechanical and thermal load effect on cutting edges during high speed hard machining process. The engagement situation was investigated in great detail using experimental and geometrical analytic measures. Experiments were conducted using A1TiN-coated micro-grain carbide end mill cutters to cut hardened die steel. On the basis, a general high speed hard machining strategy, which aimed at eliminating excessive engagement situation during high-speed machining （HSM） hard machining, was proposed. The strategy includes the procedures to identify prone-to-overload areas where excessive engagement situation occurs and then to create a reliable tool path, which has the effect of cutting load reduction to remove the prone-to-overload areas.

Mold Filling and Prevention of Gas Entrapment in High-pressure Die-casting

This paper presents some results of direct observation of mold filling in a specially designed die-casting by X-ray diffraction, including comparison with numerical simulation. Based on such work the authors discuss how to prevent gas entrapment and propose new methods.

Microstructure and properties of nano-TiN modified Ti(C,N)-based cermets fabricated by powder injection molding and die pressing

Powder injection molding （PIM） and die pressing were employed to fabricate nano-TiN modified Ti（C,N）- based cermets. The shrinkage behavior, microstructure, porosity, and mechanical properties of the samples with and without nano-TiN addition fabricated by PIM and die pressing were analyzed. It is demonstrated that for either PIM or die pressing, the porosities are obviously reduced, the mechanical properties are significantly improved after adding nano-TiN, and the hard particles are refined; the rim phase thickness obviously becomes thinner, and the number of dimples in fracture also increases. Compared the samples fabricated by die pressing, it is difficult for PIM to obtain dense Ti（C,N）-based cermets. Due to the too much existence of pores and isolated carbon, the mechanical properties of the sintered samples by PIM are inferior to those of the sintered ones by die pressing.

基于OBE理念的职教本科项目驱动式教学改革探究——以压铸模技术课程为例

依据行业发展方向,结合职业教育改革政策,从职教本科压铸模技术课程出发,以培养学生“知识+技能+创新”能力为目标,分析OBE教学理念在教学中的适用性,并从项目载体选择、项目实施、课程考核三个方面进行教学改革探索,使学生专业知识技能螺旋式提升,学习兴趣由被动变主动,创新思维得到有效锻炼,也为适应经济社会发展和技术技能的数字化设计与制造技术专业人才培养奠定基础。

职教本科背景下模具设计及制造专业课程体系的构建

明确了职教本科的人才培养定位,确定了模具专业人才培养目标,提炼了模具工艺及优化岗位、模具数字化设计岗位、模具智能化制造岗位、模具自动化生产岗位和模具信息化管理岗位等岗位所需的核心职业能力和职业素养,按照职业岗位能力和职业素养的需求设置相关课程内容,完成了职教本科背景下模具专业课程体系的构建。

基于专业教学资源库的模具拆装虚拟仿真实训构建

传统模具拆装实训受到设备条件、空间场地、安全隐患等因素影响,限制教学效果的提升。专业教学资源库、虚拟仿真系统等数字化平台的建设为该类实训的开展提供了新的载体和模式。模具专业教学资源库为该实训提供离散化、模块化的全过程数字资源支撑。虚拟仿真系统作为专业教学资源库的特色资源,为该实训提供可交互的立体操作平台。依托以上数字资源,构建了“三段式”模具拆装实训翻转课堂。

数字化转型背景下模具设计及制造专业课程体系的改革研究

明确了模具行业数字化转型背景下模具设计及制造专业人才培养目标,调研分析了模具的工艺及优化岗位、模具的数字化设计岗位、模具的智能化制造岗位、模具的自动化生产岗位和模具企业的信息化管理岗位等岗位能力,并匹配设置了支撑岗位能力的课程,完成了数字化转型背景下模具设计及制造专业的课程体系改革研究。

基于混合式教学《模具测绘技术》课程思政的研究与实践

介绍了高职模具设计与制造专业基础课程《模具测绘技术》课程思政的教学设计与实施过程。为培养德技双修,全面发展的高素质应用型人才,从行业规范、课程标准和职业能力需求出发,制定知识学习线、技能训练线、思政浸润线的“三线”共振育人的课程思政教学目标,运用现代信息技术创建多元化混合式教学方式,在教学目标、教学内容、教学方法、教学过程及教学评价中融入思政教育,形成全方位的课程思政体系。

应用型本科院校模具课程教学改革探索

结合应用型本科院校模具课程教学中存在的问题,进行了较为深入分析,提出了一些具体课程改革方法,可通过完善模具课程体系、引入3D打印、逆向技术、ANSYS、MoldFlow等新课程打造课程创新性,拓宽学生知识面。加大实践环节、深入校企合作、优化教学团队、改进教学方法、探索更适合模具课程教学的新模式。

高职模具专业“双师型”教师评价体系研究

提出了高职模具专业教师成长发展4P阶段对标“双师型”教师四级水平,探索了“双师型”教师评价体系。以“双师型”中级水平为例进行研究,通过Delphi专家咨询法对64所高职院校进行意见征询,确定包含职业品质、专业素养、教育素养、服务素养4个一级指标,对应10个二级指标,31个三级指标的评价指标集,利用层次分析法(AHP)确定各个指标的权重系数。

模具设计与制造专业班会内容与PTS人生技能课程相融合的研究

模具设计与制造专业学生的班会内容与专业拓展课《PTS人生技能》的内容相融合,先分析模具设计与制造专业的培养目标,阐述拓展课的8个模块,并以“理解和管理情绪模块”为例进行了主题班会的实施过程的介绍。班会内容与PTS人生技能课的融合是一种有益的尝试,班会中应用了课程的“演、思、说、用”4个环节。以学生为中心的理念,经验学习圈理论。让学生在班会中学习和应用人生技能,提升了个人综合素质,为学生的全面发展提供有力支持。

一体化大型压铸模具温度控制方法

新能源汽车的发展使一体化压铸完成了从0到1的突破,给压铸模具发展带来了新的机遇。压铸模具是一个热交换器,压铸模具成型中的热平衡问题至关重要。以压铸模具的温度控制为基础,介绍了压铸模具的基本概况与压铸成型加工过程中热平衡的重要性,阐述了目前一体化压铸模模温控制所采用的模温控制岛、异形水路、红外线成像技术、模内传感器、一体化压铸模模温控制集成化等方案。模具温度的控制有利于提高铸件质量,延长模具使用寿命,提高压铸效率。

模具制造技术的发展与创新

模具制造技术是现代制造业的重要组成部分,其发展和创新直接影响着制造业的生产效率和产品质量。分析了模具制造技术的发展与创新,以期为相关领域的研究者和实践者提供参考。

数控加工技术在模具制造中的应用

随着当前科技的演进,数控加工技术的出现,为机械模具的制造领域带来显著变化。通过数控技术的精细化操作,产品的质量和加工精度得到提升,同时也提高生产效率。探讨了数控加工技术在模具制造中的广泛应用及其显著优势。数控车削、电火花加工和数控铣加工等技术为模具生产提供了高精度、高效率的解决方案。这些技术的应用不仅优化了模具加工的表面质量,还通过严格控制误差和调整生产流程,确保了模具制造的精确度和效率。

技校生“金蓝领”模具特训班去“内卷”式课程考察改革实践

结合培训对象为技校生的宁海“金蓝领”模具特训班的培训实践,针对专业技能课程的学习效果考察采用去“内卷”化考察方法为主,以激发学生潜能,释放学生天赋特长,挖掘学生内在的活力,充分释放学生的个性能量,找到学生的闪光点为目标。实践证明,去内卷化的正面鼓励和表扬的考察方式更能激发学生的学习兴趣并获得较好的学习效果。

县域模具行业人才培养“金蓝领”特训班培训模式教学改革

介绍了宁海“金蓝领”特训班培训模式,该模式实事求是依据产业人才的流动规律,以及模具行业对从业人才的要求特点,打破常规模具人才培养的社培模式和高职培养模式,以县域内技工学校学生为培养对象,以着重培养学生的单项模具技能和终身职业利益为终极目标,兼顾学生的职业资格和文凭获取,为县域模具行业提供源源不断的模具基础型技能人才。该模式运行4年来,已为宁海县域模具行业提供了近200名模具专技人才,预计能有效弥补县域模具产业人才的需求缺口,有效地保证县域内模具产业的健康平稳发展。

轴承坯料机械手轴盖3D多工位级进模设计

针对轴承坯料机械手轴盖制件一套三件的成套冲压成型生产要求,运用3D设计软件UG设计了一副11工位连续级进模用于轴盖成套制件的生产。模具中所设计的11工位包括冲孔、落料、拉深、翻边、侧切、侧冲孔等工艺成型手段,模具达到的效果是材料利用率达到64.23%,制件生产效率可达45套/min,模具制造成本降低5%。相比于传统多工序多套单冲模成型工艺,生产效率提高10倍以上。模具中,使用1次拉深成型、3次精修,对多级拉深成型件进行加工能有效降低制件加工难度;使用步进电机送料,氮气弹簧压料和顶料,使模具设计难度大为降低;使用了两种楔紧块驱动型侧滑块机构对制件进行工艺面切除加工和精整形,及燕尾槽压块驱动上模侧冲孔滑块机构使制件的侧面加工得到了可靠保证。使用UG设计软件设计了模具的3D结构,较之于2D排位设计方法,更能有效避免设计缺陷,模具设计效率和可靠性更高。