Fibre-reinforced thermosets and thermoplastics containing PTFE are commonly used in marine hydropower applications due to their self-lubricating ability both dry water lubricated contacts. The constant development of such composite bearings over the last decades make them even more attractive these fields application, low maintenance cost long service life. Their tribological performance is usually estimated by extrapolation short, accelerated tests, which may induce risks inaccurate or...

This work investigates the coefficient of friction (COF) at room temperature between tool steel 1.2343 and aluminum alloys EN AW-5182, AW-6016 as-delivered (T4) naturally aged (T4*) using a strip drawing tribometer. In order to simulate contact conditions industrial sheet metal forming processes, surfaces pins strips were maintained as-delivered, i.e., wire-cut from hardened ground plate cut electrical discharge textured (EDT) dry-lubricated sheets. Two sliding velocities, 50 mm/s 250 mm/s,...

Hot stamping is characterised by severe contact conditions, especially when forming aluminium components. In order to improve the tool lifetime, process economy, and component quality, understanding initiation mechanisms behind transfer onto surface at high temperatures critical. To date, tribological interaction between tools sheets temperature has received limited attention. Lubricants, combined with engineering techniques (e.g. coatings, nitriding topography control), show great potential...

Abrasive wear in industrial applications such as mining, materials handling and agricultural machinery constitutes a large part of the total wear. Hardened high strength boron steels are known for their good resistance mechanical properties, but available results open literature scarce. This work aims at investigating how different quenching techniques affect two-body abrasive hardened steels. Furthermore, function depth thicker steel plates has also been studied. The material...

Galling is a severe form of adhesive wear associated with both cold and hot metal forming operations. In sheet Al–Si-coated ultrahigh-strength steel (UHSS), transfer occurs from the coated UHSS to tool surface. This leads poor quality produced parts, damage expensive tooling, increased downtime for maintenance tools. study thus aims at identifying salient mechanism(s), which give rise initiation/occurrence galling elevated temperatures. has been accomplished by analysing actual tools through...

Abstract Aluminium alloys are commonly used as lightweight materials in the automotive industry. This non-ferrous family of metallic offers a high versatility properties and designs. To reduce weight improve safety, strength-to-weight ratio (e.g. 6XXX 7XXX), increasingly implemented vehicles. However, these exhibit low formability experience considerable springback during cold forming, therefore hot formed. During severe adhesion (i.e. galling) aluminium onto die surface takes place....

Abstract The use of high strength aluminium alloys, such as 6XXX and 7XXX series, is continuously increasing for automotive applications in view their good strength-to-weight ratio. Their formability at room temperature limited they are thus often formed temperatures to enable production complex geometries. Critical challenges during hot forming the occurrence severe adhesion material transfer onto tools. This negatively affects tool life quality produced parts. In general, main mechanisms...

In recent years, additive manufacturing (AM) of metallic materials has achieved the production virtually fully dense parts, extending range potential applications. There is a growing interest in use AM to produce forming tools for hot stamping. The possibilities locally tailoring die material tackle wear challenges and producing more complex geometries improve cooling are key-features driving that interest. However, there lack knowledge concerning tribological behavior materials,...

In hot sheet metal forming, minimising material transfer and ensuring homogenous cooling of the workpiece are important for quality productivity reasons. The development additive manufacturing (AM) opens up possibilities novel tooling concepts by tailoring tool (new chemistries, microstructure, size/distribution hard phases) producing conformal channels. Implementing surface functionality improved tribological performance is another advantage AM. Research pertaining to high temperature...

The usage of ultra-high-strength boron steel (UHSS) in automotive industry has increased rapidly the recent past. Forming UHSS components is performed at elevated temperatures, which also offers possibility hardening through quenching directly after forming. However, influence on friction and wear during relative sliding between tool workpiece unclear. Therefore, characteristics temperatures hardened unhardened pairs are investigated this study. results show that both all affected by UHSS....

The Ni-TiO2 and Ni-CeO2 composite coatings with varying hydrophilic/hydrophobic characteristics were fabricated by the electrodeposition method from a tartrate electrolyte at ambient temperature. To meet requirements of tight regulation European Chemicals Agency classifying H3BO3 as substance very high concern, Rochelle salt was utilized buffer solution instead. novelty this study to implement simple one-step galvanostatic low-temperature based on greener compared traditionally used, aiming...

Severe adhesion, also referred to as galling, is a critical problem in press hardening, especially stamping tools used for hot forming of Al–Si-coated ultra-high strength steel. Galling known develop rapidly on the tool surface and it negatively affects quality formed products. Earlier research this topic has focused galling initiation. However, studies development during extended sliding corresponding quantitative measurement still lack depth. In present study, tribological test established...

Wheat gluten biopolymers generally become excessively rigid when processed without plasticisers, while the use of on other hand, can deteriorate their mechanical properties. As such, this study investigated effect carbon black (CB) as a filler into glycerol-plasticised to prepare gluten/CB biocomposites in order eliminate aforementioned drawback. Thus, were manufactured using compression moulding followed by determination mechanical, morphological, and chemical The content 4 wt% was found be...

Press hardening tools are expected to operate satisfactorily for thousands of forming cycles before being replaced. An approach enhance the durability in operation, and improve process economy, is refurbish them by depositing new material on tool through welding, or hardfacing, when its surface adversely damaged. The welding changes microstructure original steel deposited also has a different microstructure, as well chemical composition facilitate process. Dissimilar friction behaviour...

In hot stamping of aluminium, the need for efficient methods to evaluate, compare, and rank lubricants based on their tribological performance is critical in early stages selection. Pilot simulative testing can be costly, time-consuming, complex, making it inefficient initial benchmarking. This work aims develop a test methodology assess lubricant under key operating conditions without fully simulating forming process. The proposed method distinguishes impact temperature degradation,...

The findings in this work enhance the understanding of oxidation mechanisms and scale growth at high temperatures a strength low alloy (HSLA) steel for improving surface quality during continuous casting. phenomenon was investigated under dry air water vapor atmospheres by heating specimens 1000, 1100, 1200 °C different holding times. Temperature time had great effects on kinetics, where faster (i.e., parabolic) rates were present when compared with condition. strongly influenced number...