Due to their high specific strength, toughness, and corrosion and wear resistance characteristics, CoCrMo alloys are widely used in different industries and applications: wind turbines and jet-engine components, orthopedic implants, dental crowns, etc. The aim of this paper is to investigate the effect of lattice parameters on the compressive behavior of laser powder bed fusion (LPBF) parts from CoCrMo material. Build orientation, volume fraction, and lattice type are chosen as input parameters or control factors, and compressive yield strength (σ_y), elastic modulus (E), and specific energy absorption are chosen as the output or performance parameters for optimization. The Taguchi experimental design method is used in the arrangement of lattice parameters during experimental studies. The level of importance of the lattice parameters on σ_y, E, and specific energy absorption is determined by using analysis of variance (ANOVA). At the same material volume fractions, Diamond specimens showed higher σ_y and specific energy absorption than Gyroid and Primitive specimens, except σ_y at 0.4 volume fraction, where a Gyroid specimen showed the best result. The experimental and statistical results revealed that volume fraction and build orientation were found to be the major and minor effective factors, respectively, for all performance parameters (σ_y, E, and specific energy absorption). The effect of volume fraction on σ_y, E, and specific energy absorption was found to be 85.11%, 91.83%, and 57.71%, respectively. Lattice type was found to be the second-ranking factor, affecting σ_y, E, and specific energy absorption with contributions of 11.04%, 6.98%, and 39.40%, respectively. Multi objective optimization based on grey relation analysis showed that a Diamond specimen with 0.4 volume fraction and 45° build orientation was the best parameter set for the investigated performance outputs.

Triply periodic minimal surface (TPMS) structures offer lightweight and high-stiffness solutions to different industrial applications. However, testing of these structures to calculate their mechanical properties is expensive. Therefore, it is important to predict the mechanical properties of these structures effectively. This study focuses on the effectiveness of using regression analysis and equations based on experimental results to predict the mechanical properties of diamond, gyroid, and primitive TPMS structures with different volume fractions and build orientations. Gyroid, diamond, and primitive specimens with three different volume fractions (0.2, 0.3, and 0.4) were manufactured using a laser powder bed fusion (LPBF) additive manufacturing process using three different build orientations (45°, 60°, and 90°) in the present study. Experimental and statistical results revealed that regression analysis and related equations can be used to predict the mass, yield stress, elastic modulus, specific energy absorption, and onset of densification values of TPMS structures with an intermediate volume fraction value and specified build orientation with an error range less than 1.4%, 7.1%, 19.04%, 21.6%, and 13.4%, respectively.

Particle dampers (PD), a passive damping technology, absorb energy from particle-particle and particle-cell wall interactions originating from friction and collision. PDs offer advantages such as design simplicity, low cost, applicability in harsh conditions, and flexibility to be used in a wide frequency band range. Additive manufacturing, specifically the powder bed fusion process, can fabricate structures with integrated PDs in a single printing process, eliminating the need to implement external dampers. However, the dynamic behavior of PDs must be determined to utilize their full potential. In this study, we examined 16 cases of integrated PDs by varying specific parameters including size, number, and locations on the structure to understand the effects of these parameters on the dynamic behavior of the first and second modes of the structure. Modal tests were conducted on additively manufactured samples to extract frequency response functions and calculate modal parameters (natural frequency and damping ratio) using the rational fraction polynomial method, studying the effects of PDs. The results showed that the damping performance of the parts was increased by a factor of up to 10 using body-integrated PDs compared with the fully fused specimen. The effectiveness of body-integrated PDs was shown to be strongly dependent on their volume and location. For instance, the damping generally increased as the volume fraction increased, which also reduced the total weight of the specimens by up to 60 g. Furthermore, the damping performance significantly increased for a specific mode when the PDs were located near the maximum displacement regions.

Yüksek ısı transfer kabiliyeti, enerji absorbe edebilme ve ses izolasyonu özelliklerinden dolayı kafes yapılar havacılık, otomotiv ve biyomedikal sanayii başta olmak üzere bir çok alanda kullanılmaktadır. Kafes yapıların bu kabiliyetleri üzerinde farklı proses ve geometrik parametreler etkili olmaktadır. Farklı endüstriyel uygulamalarda, ilgili kafes yapısının uygun proses ve geometrik parametreler ile birlikte kullanılmasının, uygulama sonucu elde edilen verimi arttıracağı bilinen bir gerçektir. Bu çalışma, Taguchi deney tasarımı kullanarak, kafes yapılarda, kafes yapı çeşidinin, inşa yönünün ve hacim oranının, üretimden sonra parçada meydana gelecek çarpılma, yüzey pürüzlülüğü ve duvar kalınlık değişimi üzerindeki etkisini deneysel olarak incelemeye odaklanmıştır. Üretim için lazer toz yatağı füzyon yöntemi ve CoCrMo malzeme kullanılmıştır. Her bir parametrenin çarpılma, yüzey pürüzlülüğü ve duvar kalınlık değişimi üzerindeki etkisi ve optimum parametre seti, değişkenlerin analizi (ANOVA) metodu ile bulunmuştur. Yüzey pürüzlülüğü için en optimum parametre seti elmas kafes yapısı, 0,2 hacim oranı ve 90o inşa yönü olarak belirlenmiştir. Duvar kalınlığındaki değişim için ise en optimum parametre seti gyroid kafes yapısı, 0,4 hacim oranı ve 45o inşa yönü olarak belirlenmiştir.