Fourteen patients with displaced fractures of the humeral capitellum were treated by open reduction and internal fixation of the capitellar fragments with Herbert screws. As per Bryan and Morrey classification, there were seven type I fractures, one type II fracture, three type III fractures, and three non-unions. Patient outcomes were evaluated using the Mayo elbow performance score. The follow-up period ranged from three to seven years (mean 4.8 years). All patients had a stable, pain-free elbow with good range of motion at follow-up. There was no evidence of avascular necrosis or degenerative change.

to study the fatigue behavior of short fiber composites and validate the concept of the Master SN curve (MSNC) approach. The MSNC approach is compared with two prevalent approaches -strength based scaling and test based interpolation. The MSNC approach was found to be in a good agreement with the experimental results and was confirmed to be more accurate than the prevalent methods.

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For modelling damage in short fibre composites, both the predictions of the effective properties and the stresses in the individual inclusions and in the matrix are necessary. Mean field theorems are usually used to calculate the effective properties of composite materials, most common among them is Mori-Tanaka formulation. Owing to occasional mathematical and physical admissibility problems with the Mori-Tanaka formulation; a pseudo-grain discretized Mori-Tanaka formulation (PGMT) was proposed in literature. This paper looks at the predictive capabilities for stresses in individual inclusions and matrix as well as the average stresses in inclusion phase for full Mori-Tanaka formulation and PGMT for 2D-orientation of inclusions.The average stresses inside inclusions and the matrix are compared to solutions of full-scale FE models for a wide range of configurations. It was seen that the Mori-Tanaka formulation gave excellent predictions of average stresses in individual inclusions, even when the basic assumptions of Mori-Tanaka were reported to be too simplistic, while the predictions of PGMT were off significantly in all the cases. However, the predictions of the matrix stresses by the two methods were found to be very similar to each other. The average value of stress averaged over the entire inclusion phase was also very close to each other. Mori-Tanaka must be used as the first choice homogenization scheme.

Experiments and finite element (FE) calculations were performed to study the raster angle–dependent fracture behaviour of acrylonitrile butadiene styrene (ABS) thermoplastic processed via fused filament fabrication (FFF) additive manufacturing (AM). The fracture properties of 3D-printed ABS were characterized based on the concept of essential work of fracture (EWF), utilizing double-edge-notched tension (DENT) specimens considering rectilinear infill patterns with different raster angles (0°, 90° and + 45/− 45°). The measurements showed that the resistance to fracture initiation of 3D-printed ABS specimens is substantially higher for the printing direction perpendicular to the crack plane (0° raster angle) as compared to that of the samples wherein the printing direction is parallel to the crack (90° raster angle), reporting EWF values of 7.24 kJ m−2 and 3.61 kJ m−2, respectively. A relatively high EWF value was also reported for the specimens with + 45/− 45° raster angle (7.40 kJ m−2). Strain field analysis performed via digital image correlation showed that connected plastic zones existed in the ligaments of the DENT specimens prior to the onset of fracture, and this was corroborated by SEM fractography which showed that fracture proceeded by a ductile mechanism involving void growth and coalescence followed by drawing and ductile tearing of fibrils. It was further shown that the raster angle–dependent strength and fracture properties of 3D-printed ABS can be predicted with an acceptable accuracy by a relatively simple FE model considering the anisotropic elasticity and failure properties of FFF specimens. The findings of this study offer guidelines for fracture-resistant design of AM-enabled thermoplastics. Graphical abstract

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Short fiber reinforced composite (SFRC) materials have a different fiber orientation distribution (FOD) at every point. The fatigue properties of SFRC are known to depend on the FOD.The Master SN curve (MSNC) method for predicting an SN curve for a given FOD based on the known SN curve for the reference FOD is used to predict the local SN curve of a SFRC component by relating the damage at the microscopic level to the macroscopic fatigue properties. A simplified version of MSNC method, which needs even less experimental input, uses an assumption of constant SN curve slope is also presented in this paper. The paper validates both variants of the MSNC method on three sets of experimental data on fatigue of short fiber composites and analyses their accuracy. It is demonstrated that the MSNC approach needs only one SN curve as input with no specific requirements to the fiber orientation of the test coupon. Test coupons could have either uniform fiber orientation in the thickness or a "skin core" orientation variation. Highlights: A method for generating local SN curves for short fiber composites is presented  Method is based on combination of manufacturing studies, tests and micromechanics  Slope of SN curve is found to be independent of fiber orientation distribution(FOD)  Only one SN curve is needed as input with no restriction on FOD of reference coupon

Injection molded short fiber reinforced composites (SFRC) have different local fiber orientation distribution (FOD) at every point. SN curves of short fiber reinforced composites are known to depend on the fiber orientation distribution. Such materials also suffer from continuous loss of stiffness during cyclic loading. It is not known whether the loss of stiffness is different for SFRC with different FOD. A statistical analysis of the loss of stiffness curves is presented in this paper. Tension-tension fatigue experiments are performed and loss of stiffness is collected for every data point in the SN curve. A systematic method for comparing the loss of stiffness is developed. It is concluded that the difference in loss of stiffness curves for coupons of SFRC with different FOD is not statistically significant. Dear Editor,We, hereby submit revised version of article "A statistical treatment of the loss of stiffness during cyclic loading for short fiber reinforced injection molded composites" by the authors Atul Jain, Wim Van Paepegem, Ignaas Verpoest, Stepan V. Lomov to journal Composites Part B: EngineeringIn this paper, a new method to statistically compare the loss of stiffness curves is developed and sufficiently high number of experiments are performed to compare the loss of stiffness curves of short fiber reinforced composites. It is seen that the loss of stiffness curves are independent of the fiber orientation distribution in the short fiber reinforced composites.All the comments by all the referee have been addressed and described in the "answer to reviewer document".We declare that the content is not duplicated and not submitted to any other journal We thank the Referee for his continued interest in our work and for helpful comments that will greatly improve the manuscript and we have tried to do our best to respond to the points raised. The Referee has brought up some useful points and we appreciate the opportunity to clarify our research objectives and methods.As indicated below we have checked all the comments provided by the Referees and have made necessary changes accordingly to their indications. At the end of reply, wherever possible, we have indicated in bold the page number in text where change has been made.New text in the paper has been typed in red. Point 1: Influence of specimen extraction position (pag. 4)Profiles of the orientation tensor components over the thickness form process simulation are reported. An indication of the positions chosen for the plots of Fig.3a and Fig. 3b would be helpful for the reader. However, experimental evidence of FOD over the thickness is missing. Further, the influence of extraction position on mechanical properties is still not directly addressed. In view of this facts, it should be stated in the paper that "the FOD is uniform over the plate" is actually an assumption (supported by simulation) and that "extraction of specimens from different positions on the plate is a possible source of the scatter of quasistatic as well as fatigue strength". ...