| Aluminum Casting Technologies and Cost | | | | To develop a simulation technique to assist industry in |
| effectiveness | | | | design and optimisation of dies and products. |
| Aluminum is the established metal of choice for the | | | | This year has seen extensive developments in the |
| production of light weight components in the | | | | Smoothed Particle Hydrodynamics (SPH) code along |
| automotive, aerospace and transport industries. | | | | with testing undertaken to improve the robustness |
| Casting liquid aluminum alloys into metal moulds using | | | | and speed of modelling. Enhancements were also |
| processes such as gravity, low pressure and high | | | | made to the visualisation techniques used to display |
| pressure die casting is a cost effective means of | | | | results from SPH's three dimensional (3D) simulation |
| producing complex shapes that require minimal | | | | results. 3D SPH isothermal simulations and animations |
| machining. Australia's automotive industry supports a | | | | of parts from Nissan and Metaldyne showing complex |
| strong local aluminum die casting industry, producing | | | | filling patterns were completed. Observations by staff |
| parts that include automotive transmission housings, | | | | at Nissan Casting of the casting's filling pattern during |
| cylinder heads, inlet manifolds and engine sumps.(Ref: | | | | production were consistent with the SPH modelling |
| Growth in world automotive markets for aluminium | | | | predictions. |
| die cast components is creating significant | | | | Water analogue images from a clear perspex model |
| opportunities and challenges for the Australian | | | | of a servo piston die casting part and digitised short |
| industry, which is positioning itself as a global player. | | | | shots of an aluminium casting were completed for |
| Through partnerships between our research | | | | validation with flow predictions from SPH. The |
| organisations and key automotive participants such as | | | | validation process and further computational speed |
| Nissan and Ford, CAST has developed innovative and | | | | improvements will be completed next year. Further |
| novel technologies that have benefited our partner's | | | | developments of the SPH code particularly in the |
| productivity. In turn, these technologies have created | | | | areas of heat transfer, solidification, surface oxide |
| IP that is poised on the verge of commercialisation. | | | | prediction, robustness and speed are planned in |
| An example featured is CASTcoat a project that | | | | future work. |
| began as postgraduate research at CSIRO and The | | | | Tailoring of reform's New Die Coat for LPDC and |
| University of Queensland. It was developed further | | | | GDC |
| under CAST project funding at CSIRO with industrial | | | | To commercialise the die coat technology for low |
| trials at Nissan, Ford, Merne Products, Castalloy and | | | | pressure and gravity die casting and further improve |
| others. Now it is a provisionally patented technology. | | | | die coat properties. |
| (Ref: | | | | Industrial trials were carried out successfully in several |
| Cycle Time Reduction | | | | low pressure and gravity die casting plants. Its |
| Automated Fault Detection in Aluminium Die Casting | | | | performance was enhanced in low draft angle areas |
| Modelling of Fluid Flow Inside a Die Cavity Using | | | | of the die by application of a sealer. Two provisional |
| Smoothed Particle Hydrodynamics | | | | patents covering inventions related to have been |
| Tailoring of CAST's New Die Coat for LPDC and GDC | | | | lodged. |
| Integrated Gravity Die Design Methodology | | | | Integrated Gravity Die Design Methodology |
| Improved Quality Aluminium Automotive Castings | | | | To develop an integrated die design methodology for |
| Reduction in Metal Pressure in the HPDC Process | | | | gravity die casting that can achieve optimal die filling, |
| Cycle Time Reduction | | | | optimal feeding and yield, and dimensional stability. |
| To increase productivity of high pressure die casting | | | | A new design of feeders to address the root cause |
| by reducing casting machine cycle time by 30%. | | | | of shrinkage porosity defects in an inlet manifold |
| More than a 20% reduction in cycle time has been | | | | casting was implemented on a customer's die and |
| achieved and implemented on selected parts at two | | | | resulted in excellent outcomes. A study was |
| industry partner plants. The project has involved | | | | completed on the use of "squeeze pins" to reduce or |
| identification of opportunities to reduce the process | | | | eliminate shrinkage defects in a gravity test die. The |
| cycle time, performing research to prove the | | | | squeeze pin technique demonstrated that surface |
| concept and then carrying out the actual trial to | | | | shrinkage can be effectively eliminated and |
| prove the theoretical findings. This necessitated the | | | | associated internal micro shrinkage can be significantly |
| involvement of shopfloor staff in order to implement | | | | reduced in the locations tried. The squeeze pin |
| changes to the process. Such trials are often in | | | | concept was extended to include application as a |
| conflict with the day to day production of parts and | | | | mechanical squeeze/shear gate to reduce fettling |
| only through true cooperation has it been possible to | | | | requirement. The mechanism implemented on a test |
| achieve the project objectives. | | | | die allowed the shearing of the gate before full |
| The third year of this project has shown the | | | | solidification, with adjustment to produce variable |
| development of true cooperation between | | | | gate widths. |
| researchers and industrial partners where the latest | | | | The final part of the methodology to be developed is |
| research findings obtained through modelling and | | | | optimal die filling through variable tilt pouring from a |
| simulation have been implemented on the shopfloor | | | | ladle. To ensure smooth flow, the variable tilting |
| with the help and support of staff from Ford and | | | | motion can be programmed to match the filling rate |
| Nissan. The changes, once trialed during a production | | | | with changes in the instantaneous flow area. Flow |
| period, have been implemented as part of the | | | | evaluation is done by real time X-ray radiography on |
| process, hence providing ongoing cost benefits | | | | a test die. The effect of die geometry, especially wall |
| through a reduction in the time required to produce | | | | thickness, on die distortion will be investigated using |
| each component. | | | | computer simulation that models thermal stresses in |
| An example of implementation is a reduction in cycle | | | | casting cycles. |
| time at Nissan on a gearbox side cover produced in a | | | | Improved Quality Aluminium Automotive Castings |
| twin cavity die that has shown successful production | | | | To improve the overall performance of low pressure |
| results over many months from an original cycle time | | | | die casting operations by implementing improved tools |
| of 75 seconds down to 60 seconds. Whilst research | | | | in design and process control to reduce casting |
| at Ford on a converter housing casting has shown | | | | defects. |
| successful implementation of cycle time reduction | | | | Successful development of appropriate tooling design |
| from 90 seconds to 74 seconds. | | | | and process control has been achieved for the low |
| In future work we will look for further opportunities | | | | pressure die casting (LPDC) process to cast small |
| with current stakeholders and the die casting industry | | | | automotive components. A multi-cavity die design |
| in general, to implement the horizontal deployment of | | | | was selected and optimised by solidification simulation. |
| cycle time reduction across other machines and parts. | | | | Several dies of this design are being used to produce |
| Automated Fault Detection in Aluminium Die Casting | | | | high-volume, high-integrity parts. Casting parameters |
| To develop and implement an automatic fault | | | | were also investigated to improve the casting quality |
| detection system for surface and sub-surface | | | | and reduce the cycle time. Die trials were conducted |
| defects. | | | | on an LPDC research die to investigate the effect of |
| A fully automated fault detection machine called | | | | casting geometry and process parameters on |
| CASTvision has been developed and a prototype | | | | shrinkage defects in castings having several |
| system is ready for extended in-plant on-line trials. | | | | fundamental features of cylinder heads. The die trial |
| This project is in its third year and exciting results are | | | | successfully produced castings with shrinkage defects |
| now emerging. The results from the algorithm, which | | | | in one particular area sandwiched in the sand core, as |
| was designed and developed during the second year | | | | predicted. Analysis of castings made on the LPDC |
| of the project, have been put to the test this year. | | | | pseudo-cylinder head research die will be completed |
| Through prototyping, the CAST team have designed | | | | to establish relationships between porosity defects |
| and developed a working system, CASTvision. For | | | | and process parameters. |
| Ford's converter housing casting the off-line system | | | | Reduction in Metal Pressure in the HPDC Process |
| can detect and discriminate between defective and | | | | To investigate the role of metal pressure on the |
| good parts. The prototype system is capable of | | | | production of quality parts in high pressure die casting. |
| identifying blocked holes on any of the holes on this | | | | In the final six months of this project, effort was |
| complex casting. Off-line systems have also been | | | | focused on innovative technologies. One such |
| developed where hot tears and cold shuts can be | | | | technology was designed to absorb impact pressure |
| detected on Ford's structural sump casting. | | | | spikes that cause detrimental flashing and the other |
| Work at Nissan on their pump cover casting has | | | | technology involved revamping the hydraulics of |
| resulted in a CASTvision prototype system for in-line | | | | ageing die casting machines to improve product |
| fault detection. The system is able to capture images | | | | quality. A novel shock absorbing technology was |
| and identify certain categories of defects on the | | | | developed that utilised existing casting overflows. Die |
| surface of the part. This project has demonstrated | | | | casting trials at CSIRO confirmed the effectiveness |
| that advances in machine vision applied to fault | | | | of this technology in absorbing impact pressure |
| detection of aluminium castings can be taken from | | | | shocks upon cavity filling. Through in-plant trials at |
| the concept stage through to a working prototype | | | | Nissan Casting Plant the limits of hydraulic valve timing |
| very successfully. The next step for this project is to | | | | and circuit functioning were confirmed. A proposal for |
| take the concepts from single part to multi part | | | | a revamp to improve intensification pressure |
| systems able to handle more complex shapes and | | | | response was put forward. The project concluded in |
| surfaces. This outcome will be a strong candidate for | | | | December 2001. Ford Australia may adopt the |
| future commercialisation. | | | | reduced pressure operating parameters for the |
| Modelling of Fluid Flow Inside a Die Cavity Using | | | | production of their new Barra model engine sumps |
| Smoothed Particle Hydrodynamics | | | | later in 2002. |