Fatigue strength of diamond coatings' interface assessed by inclined impact test

Bouzakis, K.‐D.; Skordaris, G.; Bouzakis, E.; Makrimallakis, S.; Kombogiannis, S.; Lemmer, O.

doi:10.1016/j.surfcoat.2013.09.030

Cited by 21 publications

(24 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As discussed in Ref 2,26, depending on the applied impact load, a fatigue failure of the NCD coating-substrate interface develops after a certain number of impacts leading to the coating detachment. This happens, if the developed interface stresses exceed the interfacial toughness of the NCD coating quantified by SFLS ( Ref 2,21,26). After the coating-substrate interface failure, the highly compressive stresses in the NCD coating structure are released elevating the detached coating region (bulge formation) at a certain maximum height.…”

Section: Introductionmentioning

confidence: 95%

Temperature-Dependent Fatigue Strength of Diamond Coating-Substrate Interface Quantified via the Shear Failure Stress

Skordaris

2015

J. of Materi Eng and Perform

Self Cite

View full text Add to dashboard Cite

A dynamic 3D-finite element method (FEM) thermomechanical model is employed for quantifying the temperature-dependent fatigue strength of nanocrystalline diamond (NCD) coating-substrate interface. This model simulates dynamically the inclined impact test on NCD-coated cemented carbide inserts considering the temperature-dependent residual stresses in the NCD coating structure. A fatigue damage of the NCD coating-substrate interface develops after a certain number of repetitive impacts depending on the applied impact load and temperature. After the interface fatigue failure, the high compressive residual stresses of the NCD coating structure are released, and the detached coating hikes up at a certain maximum height (bulge formation). The critical impact forces for avoiding the fatigue failure of the NCD coatingsubstrate interface, and the subsequent film detachment after 10 6 impacts at various temperatures were determined by conducting inclined impact tests up to 400°C. Considering the critical impact forces, using the mentioned FEM model, the related shear failure stresses in the NCD coating-substrate interface at various temperatures were predicted.

show abstract

Section: Introductionmentioning

confidence: 95%

Temperature-Dependent Fatigue Strength of Diamond Coating-Substrate Interface Quantified via the Shear Failure Stress

Skordaris

2015

J. of Materi Eng and Perform

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, after machining a further 400 holes, the occurrence of peeling suggests that the adhesive strength of the coating does not suffer from the drilling force that always keeps a constant value, implying that one possible reason is the decrease in the adhesive strength of the coating during drilling. Hence, we believe that fatigue strength [31,32], rather than adhesive strength, may be more suitable to evaluate the mechanical behavior of coatings when it drills the holes again and again. Certainly, adhesive strength is also vital in terms of the peeling of the coating, which can be proven by our experimental results of the MCD coating.…”

Section: Fatigue Strength and Contact Mechanics Of Diamond Coatingmentioning

confidence: 99%

“…According to the principles of the mechanics, the peeling derived from the mismatch between the external force and the adhesive strength of the coating. Fatigue behavior weakened the resistance to external force as the adhesive strength decreased [31]. In this work, the Hertz elastic model and stress of two contact materials [33] (Figure 7) were employed to evaluate the mechanical trend of the coating during wear.…”

Section: Fatigue Strength and Contact Mechanics Of Diamond Coatingmentioning

confidence: 99%

Influence of Adhesive Strength, Fatigue Strength and Contact Mechanics on the Drilling Performance of Diamond Coating

Liu

2020

Materials

View full text Add to dashboard Cite

Adhesive strength of the coating significantly affects the lifetime of the coating. However, it is still inevitable for the coating, even with strong adhesive strength, to peel off from the substrate after working for a while. In this work, fatigue and wear behaviors were employed to analyze the effect on the mechanics of coating and contribute to a fundamental understanding of peeling of the coating. A small-size Co-cemented tungsten carbide drill bit was selected as the examined substrate to fabricate the diamond coating. Roughening pretreatment with a diamond slurry combined with ultrasonic vibration was performed for the substrate surface to enhance adhesive strength. Meanwhile, a diamond coating without roughening pretreatment was also fabricated for comparison. The lifetime and quality of the coating were evaluated by the drilling test. Although the diamond coating could grow on the substrates with and without roughening pretreatment, the diamond coating with roughening pretreatment possessed a higher lifetime and stronger wear resistance than that without roughening pretreatment. We found that both substrates with and without roughening pretreatment exhibited a coarse surface, whereas the roughening pretreatment could remove the original machined surface of the substrate and thus make the near surface with numerous integrated crystalline grains become the new topmost surface. This increased the contact area and surface energy of the interface, leading to the improvement of adhesive strength. Finally, fatigue strength and contact mechanics were studied to trace the changes in the stress of the diamond coating in the whole process of drilling from a theoretical point of view. We suggest that fatigue strength and contact mechanics may play vital roles on the durability and peeling of the coating.

show abstract

“…After the interface fatigue failure, the high compressive residual stresses of the diamond structure are released, and the detached coating hikes up at a certain maximum height (bulge formation). Based on a developed FEA model described analytically in [11], which simulates the film lifting after the fatigue failure of its interface and the residual stress release, the overall residual stresses in the film structure were calculated (see figure 2). Moreover, the thermal residual stresses were determined with the aid of an additional FEA model [11].…”

Section: Characterization Of the Investigated Diamond Coatings 31 Rementioning

confidence: 99%

“…Based on a developed FEA model described analytically in [11], which simulates the film lifting after the fatigue failure of its interface and the residual stress release, the overall residual stresses in the film structure were calculated (see figure 2). Moreover, the thermal residual stresses were determined with the aid of an additional FEA model [11]. These stresses are shown in figure 2.…”

Section: Characterization Of the Investigated Diamond Coatings 31 Rementioning

confidence: 99%

Effect of the crystallinity of NCD and MLD diamond coatings characterized by same level of residual stresses after annealing on their fatigue strength and wear behavior in milling

et al. 2020

View full text Add to dashboard Cite

Nano-composite (NCD) and multi-layered (MLD) diamond coatings were deposited on cemented carbide tools using hot filament chemical vapour deposition (HFCVD) techniques. Appropriate annealings were conducted on the examined diamond coatings in order to be characterized by the same level of residual stresses. The crystalline structure of the employed diamond coatings was investigated by conducting Raman spectra. Inclined impact tests at ambient and elevated temperatures were carried out for assessing their temperature-dependent fatigue strength. Moreover, the wear behaviour of diamond coated inserts was investigating in milling aluminum foam. Raman spectra were also conducted on the treated diamond coatings for capturing potential crystalline changes developed due to the exercised thermal and dynamic mechanical loads during cutting. According to the attained results, the coexistence of sp2– and sp3-bonded phases in the cases of MLD diamond coatings results in an accelerated wear development, despite their structure capability to decelerate the crack propagation. As a result, nano-crystalline diamond coatings characterized only by sp3-bonded phase exhibit an improved wear behaviour. The cutting performance of the NCD coated inserts is further improved due to the enhanced tribological properties of the NCD coatings.

show abstract

Fatigue strength of diamond coatings' interface assessed by inclined impact test

Cited by 21 publications

References 19 publications

Temperature-Dependent Fatigue Strength of Diamond Coating-Substrate Interface Quantified via the Shear Failure Stress

Temperature-Dependent Fatigue Strength of Diamond Coating-Substrate Interface Quantified via the Shear Failure Stress

Influence of Adhesive Strength, Fatigue Strength and Contact Mechanics on the Drilling Performance of Diamond Coating

Effect of the crystallinity of NCD and MLD diamond coatings characterized by same level of residual stresses after annealing on their fatigue strength and wear behavior in milling

Contact Info

Product

Resources

About