Fredrik Svahn

The influence of surface roughness on friction and wear of machine element coatings

Demands on lower fuel consumption, reduced pollution, increased operating times, etc. force the automotive industry to constantly improve the performance of critical machine elements. In this development various carbon based coatings have proven very promising, mainly because of their low friction and high wear resistance in dry sliding contacts. The contact conditions can be very different in various machine element applications, e.g. both rolling and sliding contacts. Additionally, most contacts are usually lubricated. Hence, other properties of the coating may be required in order to obtain low friction and wear, as for instance a beneficial running-in ability. In lubricated contacts the very high wear resistance of carbon coatings can cause fatigue damage resulting in delamination of the coating, especially when deposited on rough substrates. In rolling contacts the fatigue damage can be reduced simply by using smoother surfaces, but the thickness of both the coating and the interlayer also has a strong influence on fatigue damage.In lubricated sliding contact tests it was found that the running-in ability could be improved by modifying the coating and/or by using an appropriate surface preparation prior to coating deposition. An increased Cr-content in the top-layer of the carbon coating reduced the friction due to the formation of a stable tribo-layer on the uncoated counter body. An even further reduced friction could be obtained by employing a fine wet-blasting of the substrate giving sharp surface asperities. The friction reduction is thought to be a result of a transition towards a higher degree of full film lubrication, due to a very fine smoothening process of both the coating and the counter body during the running-in process.

Capability search and redeem across digital ecosystems

Prior research on digital ecosystems focuses on the focal firm (e.g., a platform owner) and its ecosystem governance. However, there is a dearth of literature examining the non-focal actor, that is, an ecosystem participant who is at the periphery of a digital ecosystem. This paper proposes a theoretical perspective of the non-focal firms participation across digital ecosystems for cultivating its innovation habitat through capability search and redeem. Capability search involves the location of external capability deemed valuable for extending the firms innovation habitat. Capability redeem refers to the firms use of external capability to develop, distribute, and/or monetize its products and services. We generate and sensitize the proposed perspective in the context of Sony Ericssons innovation habitat by interpreting the mobile device manufacturers participation across four digital ecosystems (Visual Basic, Java, Digital Music, and Android). Our findings suggest that the non-focal actor cannot rely on a single ecosystem for addressing all relevant layers of innovation. It benefits from pursuing a pluralistic strategy, operating across digital ecosystems to avoid investing all efforts in the same ecosystem. The model of ecosystem capability search and redeem, which is a result of ideographic research explanation, extends current perspectives on digital ecosystems and contributes to the emerging literature in the digital age.

The Dual Regimes of Digital Innovation Management

The pervasive integration of digital technology in traditionally physical products such as cars, heat pumps, and washing machines calls for revisiting the received innovation literature. To this end, this paper presents a competing logic framework for understanding digital technology in product innovation management. In doing this, we derive two idealized innovation regimes by distinguishing and assessing two broad streams of innovation research across the dimensions of organizing logic, market dynamics, and architectural design. Recognizing and elaborating inherent tensions between product innovation and IT innovation, the framework identifies a range of new challenges with implications for digital innovation management research and practice.

Structural change of biomimetic hydroxyapatite coatings due to heat treatment

Biomimetic deposition of hydroxyapatite (HA) coatings on implants could be done for two reasons, one is to study their possible bioactivity, and one is to generate bioactive coatings on implants before implantation surgery to improve the osseointegration. Heat treatment of coated implants can be performed for several reasons, for example, to ensure coating sterility and to increase the adhesion. This paper describes the morphology and crystalline structure changes occurring due to the heat treatment of biomimetic HA coatings on rutile TiO2. Rutile TiO2 surfaces were produced on titanium (Ti) plates by heating at 800 degrees C. Afterwards, these samples were immersed in a phosphate buffer saline solution for 7 days at 37 degrees C in order to deposit HA coatings on their surfaces. These HA coatings were then either untreated or heat treated at 600 or 800 degrees C for 1 hr. The coatings microstructural changes were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cross-sectional TEM samples were produced using a sample preparation method based on focused ion beam microscopy (FIB). Rutile was found to be bioactive due to HA formation on the surface. The 600 degrees C heat treatment of the HA coating changed its morphology, increased its grain size and also increased the porosity. At 800 degrees C the coating was completely transformed to beta-TCP according to XRD. Sample preparation using FIB and TEM analysis proved to be a useful method for high-resolution analysis of biomimetic coatings in cross-section.

Novel load-carrying layers to support low-friction PVD coatings

Five different materials have been studied with respect to their load-carrying capacity together with PVD coatings. The materials were mild carbon steel, hardened and annealed ball bearing steel, a thick electro-deposited Ni coating, and plasma-sprayed alumina coatings with and without the pores and cracks sealed with electro-deposited Ni. The two latter materials have not previously been studied in this respect. A WC-doped hydrogenated diamond-like carbon (Me-C:H) coating was deposited on each material. All materials were subjected to mechanical and tribological testing, including scratching, nanoindentation and pin-on-disc testing. The sealed plasma-sprayed alumina coating, as well as the unsealed, behaved surprisingly well as load carriers for PVD coatings, despite their porosity and low cohesion. The overall trend was that hard materials generally functioned better than soft ones. However, there is at present a small risk of chipping of the sprayed materials, which can be reduced by future process optimisation.

Applying Options Thinking to Shape Generativity in Digital Innovation: An Action Research into Connected Cars

Although extant research convincingly argues that managers can change product innovation practices by exploiting new forms of generativity afforded by digital technology, the literature has so far been silent on how incumbent firms may conceive of and implement requisite generative capability. Against this backdrop, we report from an action research study into a digital innovation initiative aimed at developing connected cars. The managers in charge of the initiative engaged us as they faced considerable skepticism and push-back from the organization. To help the firm embrace new innovation norms and practices, we therefore infused innovation theory and options thinking into the group of managers as a means to conceive of and implement generative capability. As a result, we present and validate an integrative theoretical model of how incumbent firms may leverage digital options thinking to shape their organizational and technological resources into requisite generative capability. In conclusion, we discuss the contributions of the model and the empirical results to extant literature on generative capability in digital innovation.

Characterization of the Tissue-Bioceramic Interface In Vivo Using New Preparation and Analytical Tools

A key feature in the understanding of the mechanisms of integration of implant materials is a deepened in-sight of the elemental and molecular composition of the interface zone between the implant and tissue. To analyze the interface at the ultrastructural level, transmission electron microscopy (TEM) is needed. However, techniques to fabricate thin foils for TEM are difficult and time consuming. By using focused ion beam microscopy (FIB) for site-specific preparation of TEM-samples, intact interfaces between bioceramics and calcified tissue can be prepared. The site-specific accuracy of the technique is about 1 mm. By using a dual-beam FIB, which is a combined scanning electron and focused ion beam microscope, the sample can be imaged with both electrons and ions (generating both secondary electrons and ions). Results from interface studies between Ca-aluminate based orthopaedic cement, dental materials, HA-coated Ti-implants and bone are presented. The interfaces were imaged in scanning-TEM and bright field mode, the crystal structures were determined using electron diffraction and elemental composition analyzed with energy dispersive spectroscopy. The technique fulfils a demand to correlate the surface properties of bioceramic implants with the structure and composition of preserved interfaces with tissues.

Platform Thinking in Incumbent Firms: From Concept to Capability

Incumbent firms struggle with new forms of competition in today’s increasingly digital environments. To leverage the benefits of innovation ecosystems they often shift focus from products to platforms. However, existing research provides limited insight into how firms actually implement this shift. Addressing this void, we have conducted a comparative case study where we adopt the concept of platform thinking to comprehend what capabilities incumbents need when engaging in innovation ecosystems and how those capabilities are developed.