Presshardened bearing components

Project time: 2010 – 2012

Budget: 3 883 000 SEK

Funding: FFI – Strategic Vehicle Research and Innovation

The press hardening process is based on the forming of hot blanks, in the austenitic state, to improve the formability as well as obtaining a final martensitic structure by subsequent rapid cooling in the forming tools

Gestamp HardTech invented the press hardening technology in the 1970’s. One used technology at SKF is cold stamping. The sheet steel could be used both for a bearing house or raceway for different bearing applications. Today the manufacturing of stamped bearing applications could be based on cold forming followed by heat treatment. In some cases this is followed by processes like grinding and polishing. The output from this manufacturing process can sometimes be sensitive to distortion. The aim of the project was to evaluate if the press hardening technique could be used for bearing applications. The use of press hardening was believed to improve form stability and thereby enhance productivity. Also it was judged to reduce process steps since pressing and hardening was made simultaneously. This could give economical, logistical and environmental advantages. The material used was chromium alloyed sheet metal. The addition of chrome can be beneficial when to quenching the material in the cold tools. By using the press hardening technology a less alloyed material could be used. This was seen as an environmental advantage. The project involved choosing two different bearing applications and modifying their geometry to better suit the press hardening process. The first bearing application (included in Work Packages 1-4) was performed as an internal project at Gestamp HardTech except Work Package 4, which contained the cost analysis and process definition of the serial production. For the second application a materia l was chosen and thoroughly investigated in terms of mechanical properties and behavior during and after forming/hardening. Prototypes were manufactured and measured. The tools were adjusted and new prototypes were made. One problem with the prototypes was draw marks on surfaces with high requirements on the surface finish. Different coatings on some of the tool surfaces were tested to see if the draw marks could be reduced. The prototypes did not meet all of the requirements. They showed good potential regarding the form tolerances but did not meet the other requirements. On some of the areas where high hardness is required there are some local softer spots. These are believed to derive from a poor process tool contact. To reach the requirements on the prototype it was thought that a material with higher alloy content would be better suited for the chosen geometry. Process layouts were made for the possible processes of the two bearing applications. New ways to shorten the cycle time for the products and decrease the amount of work in process by using new technologies for heating and cooling was investigated.

Participating researcher(s)

Partners

Share

Similar projects

Geometry optimized adhesive joining for sustainable production

"Geometry Optimised adhesive joining for sustainable production” in Swedish (Geometri Optimerad LimFogning för hållbar produktion, "GOLF") is a project within the Swedish research program FFI for Sustainable production. It has as its mission to develop technology and methods to get the right amount of adhesive on the right place. The drivers behind this are the overall strive to decrease weight in vehicles and moving machines to minimize the amount of CO2 in the atmosphere.

2013 – 2015

Automotive components from renewable resources with good barrier properties and tailored biodegradability, for interior applications

Our hypothesis is that advanced, lightweight, multi-layer-structured composites with good barrier properties and tailored biodegradability can be produced by combining bio-based thermoplastic with special additives and pulp fiber mats. This material is free from fossil raw materials, sustainable, fire and impact-resistant and suitable for interior components in vehicles.

2012 – 2013

Emerging digital technologies and their applicability as picking support in materials handling

In material handling processes, such as kitting and sequencing, which are used in the automotive industry to supply the assembly with a wide and growing range of component variants, the picking information system is central design aspect. Given the developments in digitization, the purpose of this concept study is to evaluate the potential of digital technology to support materials handling work in production systems.

2017 – 2017

PADOK – Study Visit to India 2016

With globalization and other megatrends as demographic changes and climate change, more knowledge is needed regarding production in an international perspective. PADOK Study Visit in India 2016 have given an increased knowledge regarding how production is conducted in India, some of the challenges producing companies in that region is facing and how Swedish companies interested in investing in production in India could act to establish themselves in the region.

2016 – 2016

Dense-Arc joining of hybrid thermoplastic composite-metal structures (DENSARC)

The aim with the project is to test a new method to join thermoplastic composite to metal in a lap joint by using a focused TIG arc, as a heat source, to heat the metal side just enough so that the composite melts and join to the metal. The method gives single sided access, no need for additional filler material and makes invisible joints possible. The objective is to have a joining method that is robust, gives high productivity and high quality as well as cost advantages.

2012 – 2013

Virtual PaintShop – Simulation of Oven Curing

The paintshop is often a bottleneck in production and the processes are fine-tuned based on testing on numerous prototypes. To meet the future demands there is a great need to improve the product preparation process. The aim is to develop methods, techniques and software, and supporting measurement methodology, for simulation of paint curing in IR and convective ovens. The goal is to assist the industry to further develop and optimize their surface treatment to be more energy and cost efficient; to have a shorter lead time in product development; and to give a higher product quality.

2016 – 2019

Virtual PaintShop – Simulation of Oven Curing

Sintered parts with high static loading capacity

The project has confirmed the hypothesis that tailoring of the tempering is a functioning means of making PM steel sustainable towards high static loading in potential automotive applications. The project has also developed further understanding about mechanisms that could be responsible for static loading sensitivity with respect to creep/relaxation at slightly elevated temperature. The results relate to sustainable manufacturing processes, the basis being that powder compaction and sintering is an energy efficient way with high raw materials utilization.

2012 – 2013

Sustainable Manufacture of Future Engine Components

The project has addressed challenges in casting and realisation of new cast irons with improved properties and machinability, decision making regarding manufacturing strategies and machinability of materials. Silicon-alloyed compacted graphite iron (CGI) has been demonstrated av new alternative for future engine components. New simulation technique for assessing manufacturing strategies has been introduced. Generic know ledge has been developed w hen it concerns w ork material machinability w ith specific reference to combined materials in advanced components.

2012 – 2015

Streamlined Modeling and Decision Support for Fact-based Production Development (StreaMod)

The integration of data management systems, simulation software and optimization algorithms have been shown to increase throughput in existing production but also allow expanded use of virtual tools in the preparation phases. This in turn leads to shorter development times for new production systems and products. The project has also contributed to greater understanding and concrete improvements in the processes of collecting and assure the quality of production data. This in turn increases the quality in both simulations and direct data-driven analyzes.

2013 – 2017

Compact and energy efficient transmissions – control and prediction of functional surface behavior

The overall objective of the project was to: • Develop simulation methodology for drive simulation of transmissions with given shape, surface topography and surface structure, - for more robust and better prediction of the efficiency and life of gear contacts in gearboxes. • Through experimental evaluation and characterization, support and verify the developed simulation technology • Through experimental evaluation and characterization, further verifying the potential of using the correct surface texture, e.g. honing, and right-handed gear in heavy-duty transmissions.

2016 – 2018