Heat Treatment Method Research Articles

Nitrogen diffusion along the layer boundaries after nitriding of multilayer materials

Diffusion processes play a key role in formation of the structures of new materials and technological processes of strengthening heat treatments, since diffusion is the reason for redistribution of substances in solids. An urgent task is to develop technologically advanced and effective methods for strengthening materials in order to improve their performance properties. There is an increasing need to improve chemical heat treatment methods, which directly affects the wear resistance of working surfaces, and, consequently, the product service life. Near-surface volumes experience increased loads, so the formation of high-strength layers becomes an important task. Quite a few methods of surface hardening are known, among which carburization, nitriding, nitrocarburization and others are widely used. The most interesting is nitriding, since it increases hardness, strength, fatigue limit, and heat resistance. However, despite the proper advantages, nitriding has a number of disadvantages, including the holding duration and small thickness of diffusion layers. The solution is related to intensification of the technological process by increasing the nitriding temperature, activating the nitriding media or directly the parts surface. All these solutions are aimed at accelerating diffusion processes, both in grain volume and along grain boundaries, the velocity along which is many times higher than the velocity of volumetric diffusion. It may be effective to use a new type of structural metal materials with a multilayer structure of hundreds of layers, with thicknesses in the micron and submicron ranges separated by large angular boundaries. The results of metallographic studies showed the effect of the steel layers interchange in the multilayer metal material on diffusion depth after chemical heat treatment. The authors proposed an accelerate diffusion model of diffusible element along the layer boundaries.

Study on Effects of Hydrothermal Heat Treatment Method on Fertilizer Efficiency of Biomass Waste

This study explores a new way of utilizing biomass waste as fertilizer based on the hydrothermal heat treatment method. Hydrothermal heat treatment was carried out on common biomass waste, including corn stalks, livestock manure, and vegetable waste. by heating them to 120°C and then to 240°C respectively, while measuring the contents of organic matter, total nutrients, and humus in hydrothermal solid products. The experimental results are as follows. With the increase in temperature, the pH of three kinds of biomass waste hydrothermal products is reduced to different degrees. The content of organic matter in the solid products of corn stalk increased with the increase of temperature, the content of organic matter in the hydrothermal products of vegetable waste was opposite to that of corn stalk, and the content of organic matter in the hydrothermal solid products of pig manure was higher than 30% at different temperatures. The total nutrient content of the hydrothermal product of corn stalk decreased first and then increased with the increase of temperature, and reached the minimum value of 10.12 g/L at 180°C. The total nutrient content of the solid product of vegetable waste showed a negative correlation with temperature, and the total nutrient content of the raw material of pig manure was 60.55 g/kg. The total nutrient content of solid products after different hydrothermal temperature treatments was 41.8–59.03 g/kg, which was lower than that of raw materials. With the increase of temperature, the humic acid content of the solid product of corn stalk first increased and then decreased, the humic acid content of hydrothermal product of pig manure continued to increase with the increase of temperature, and the humic acid content of hydrothermal product of vegetable continued to increase with the increase of temperature. At 210°C, the contents of humic acid and fulvic acid reached the maximum, and the humification rate reached the maximum of 0.856.

Synthesis and full-spectrum-responsive photocatalytic activity from UV/Vis to near-infrared region of S-O decorated YMnO3 nanoparticles for photocatalytic degradation of ibuprofen.

The oxalic acid complexation method and sulfuric acid heat treatment method were used to synthesize the YMnO3 (YMO) and YMO-SO4 2- (YMO-SO) photocatalysts. The YMO-SO photocatalyst maintained the crystal structure of YMO, but the particle size increased slightly and the optical band gap decreased significantly. The YMO-SO photocatalyst demonstrates a wide range of light absorption capabilities, covering ultraviolet, visible and near-infrared light. The photocatalytic activity of YMO-SO was investigated with ibuprofen as the target pollutant. The YMO-SO photocatalyst exhibits high ultraviolet (UV), visible and near-infrared photocatalytic activity. Experiments with different environmental parameters confirmed that the best catalyst content was 1g/L, the best drug concentration was 75mg/L and the best pH value was 7. The capture experiment, free radical detection experiment and photocatalytic mechanism analysis confirmed that the main active species of YMO-SO photocatalyst were hole and superoxide free radical.

The effect of ohmic heating conditions and heating modes on gel properties of unwashed pre-rigor common carp (Cyprinus carpio) surimi.

Ohmic heating (OH) at different conditions (voltage: 15, 20, 25V; frequency: 1, 5, 10kHz) and one-step water bath (WB) were used to heat wash and unwash surimi prepared from fresh pre-rigor common carp. The optimal heating conditions were established through assessments of gel strength, Texture Profile Analysis (TPA), water-holding capacity (WHC), whiteness, and sensory evaluation. Then, the impact of heating modes on gelation properties of unwashed surimi based on the optimal heating conditions was investigated. The study findings indicated a significant enhancement in gel properties compared to WB. Unwashed surimi gel properties showed improvement when derived from freshly caught raw fish and subjected to OH treatment. Moreover, variations in frequencies and voltages were observed to influence the heating rate. Optimal gel quality was achieved at 10kHz 20V (10V/cm), facilitating swift progression through the gel deterioration stage, inhibition of protein hydrolyzing enzymes activity, and establishment of a stable gel network. Continuing to increase the heating rate would disrupt its network structure, resulting in diminished gel strength and WHC. The best quality of unwashed surimi gel was achieved by heating to 40°C for 30min, followed by heating to 90°C for another 30min (40°C 30min+90°C 30min) under 10kHz 20V. The gel strength increased when held for 1h at 40°C. For optimal heating efficiency, the heating mode of 40°C 30min+90°C 30min is recommended to prepare unwashed surimi gel. PRACTICAL APPLICATION: Ohmic heating, as a rapid food heat treatment method, can both increase the heating rate and improve the gelation properties of freshwater surimi. There is a wide range of potential applications for the heat treatment of the surimi.

Effects of Nanocomposite Derivatives of Ni-Fe, Ni-Co, Ni-Co-Fe Prussian Blue Analogues on the Thermal Decomposition Performance of Nitrocellulose.

The incorporation of nanomaterials generated from Prussian blue (PB) derivatives has emerged as a promising strategy to significantly improve the properties of energetic materials. In this study, we comprehensively investigated the influence of nanomaterials derived from PB on the thermal decomposition characteristics of energetic materials. To achieve this goal, we prepared nanomaterials using coprecipitation and heat treatment methods with PB derivatives as catalysts. Advanced techniques such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller (BET) analysis for specific surface area and pore size, and X-ray photoelectron spectroscopy were employed to thoroughly characterize these nanomaterials. Differential scanning calorimetry was used to assess the thermal behavior of nitrocellulose (NC), and the relevant kinetic parameters were determined through thermal decomposition kinetics calculations and analysis. This work revealed the influence of catalysts on the NC decomposition process and provided comprehensive insights into the effect of integrating nanomaterials derived from PB derivatives on the thermal decomposition performance of NC. The results of this work demonstrated the possibility of using nanomaterials generated from PB derivatives as effective catalysts to enhance the thermal decomposition characteristics of NC, offering interesting opportunities for their application in the field of high-energy materials.

Investigation of Si, Mn, and C interactions during coiling of hot rolling model alloys

Model alloys were developed to investigate the interaction of Mn, Si, and C during hot rolling. The alloy samples prepared by the method of vacuum-sealed tube heat treatment exhibited unique microstructural features: surface reduced Fe layer, interface reduced Fe layer and internal oxidation layer. The experimental results revealed that scale reduction is mainly controlled by the effect of Si and decarburization behavior, as well as the contribution of Si is more significant. The competing reactions of decarburization substantially reduce the depth of internal oxidation of the alloy. Additionally, combination of Mn and Si greatly facilitated the process of internal oxidation, with Si playing a role in inducing the inward oxidation of Mn. These insights will contribute to a better understanding of hot rolling coiling process, especially the complex interactions of Mn, Si, and C.

Instantaneous Thermal Energy for Swift Synthesis of Single-Atom Catalysts for Unparalleled Performance in Metal-Air Batteries and Fuel Cells.

Based on experimental and computational evidence, phthalocyanine (Pc) compounds in the form of quaternary-bound metal-nitrogen (N) atoms are the most effective catalysts for oxygen reduction reaction (ORR). However, the heat treatment process used in their synthesis may compromise the ideal structure, causing the agglomeration of transition metals. To overcome this issue, a novel method is developed for synthesizing iron (Fe) single-atom catalysts with ideal structures supported by thermally exfoliated graphene oxide (GO). This is achieved through a short heat treatment of only 2.5min involving FePc and N, N-dimethylformamide in the presence of GO. According to the synthesis mechanism revealed by this study, carbon monoxide acts as a strong linker between the single Fe atoms and graphene. It facilitates the formation of a structure containing oxygen species between FeN4 and graphene, which provides high activity and stability for the ORR. These catalysts possess an enormous number of active sites and exhibit enhanced activity toward the alkaline ORR. They demonstrate excellent performance when applied to real electrochemical devices, such as zinc-air batteries and anion exchange membrane fuel cells. It is expected that the instantaneous heat treatment method developed in this study will aid in the development of high-performing single-atom catalysts.

Adjusting laser power to control the heat generated by nanoparticles at the site of a patient's cells.

Cancer treatment often involves heat therapy, commonly administered alongside chemotherapy and radiation therapy. The authors address the challenges posed by heat treatment methods and introduce effective control techniques. These approaches enable the precise adjustment of laser radiation over time, ensuring the tumour's core temperature attains an acceptable level with a well-defined transient response. In these control strategies, the input is the actual tumour temperature compared to the desired value, while the output governs laser radiation power. Efficient control methods are explored for regulating tumour temperature in the presence of nanoparticles and laser radiation, validated through simulations on a relevant physiological model. Initially, a Proportional-Integral-Derivative (PID) controller serves as the foundational compensator. The PID controller parameters are optimised using a combination of trial and error and the Imperialist Competitive Algorithm (ICA). ICA, known for its swift convergence and reduced computational complexity, proves instrumental in parameter determination. Furthermore, an intelligent controller based on an artificial neural network is integrated with the PID controller and compared against alternative methods. Simulation results underscore the efficacy of the combined neural network-PID controller in achieving precise temperature control. This comprehensive study illuminates promising avenues for enhancing heat therapy's effectiveness in cancer treatment.

Ru and Ruδ+ synergistic catalysis efficiently promotes 2,2,6,6-Tetramethyl-4-Piperidone hydrogenation for 2,2,6,6-Tetramethyl-4-Piperidinol preparation

The catalytic hydrogenation of nitrogen-containing heterocyclic compounds is a crucial process; however, nitrogen removal severely restricts product selectivity. Consequently, this study utilized a simple heat treatment method to synthesize ruthenium (Ru)-based catalysts supported on N-doped activated carbon for application in the selective catalytic hydrogenation of 2,2,6,6-Tetramethyl-4-piperidone (TAA). The results show that the selectivity of 2,2,6,6-Tetramethyl-4-piperidinol (TMP) is as high as 99.87 % under the premise of almost complete TAA reaction. The catalyst was characterized using N2-physisorption-desorption, XRD, TEM, Raman, XPS, ICP-OES, and H2-TPR techniques. N-doped activated carbon introduced numerous defect sites to the catalyst, improved the surface wettability of the activated carbon support, provided abundant active metal anchoring sites, which results in highly uniform dispersion of Ru nanoparticles (NPs) on the carrier surface, forms relatively smaller nanoparticles, and enhances the catalyst's activity. Additionally, a strong interaction exists between the active metal Ru and N-doped activated carbon support. Thus, the transfer of free electrons from Ru to N species was facilitated, and the relative content of Ruδ+ in the catalyst was increased, and the synergistic effect between Ru and Ruδ+ contributes to improving the catalyst's performance. This work holds significant potential for controlling the selectivity of nitrogen-containing heterocyclic compounds in the catalytic hydrogenation process.

Effect of Y2O3 on crystallization and mechanical properties of sodium aluminum silicate glass containing ZrO2

In this paper, high transmittance glass-ceramics containing Zirconium Yttrium Oxide (Zr0.82Y0.18O1.91) nanocrystals were successfully prepared by melt cooling and crystallization heat-treatment method. The effects of Y2O3 concentration on the structure, crystallization performance, transmittance, and indentation fracture toughness of Na2O–Al2O3–B2O3–SiO2–ZrO2 glass and glass-ceramics were explored. The addition of Y2O3 improved the Vickers hardness (4.81 GPa–5.25 GPa) and indentation fracture toughness (0.78 MPam1/2 to 0.95 MPam1/2) of the glasses. Y2O3 successfully facilitated the precipitation of the non-alkaline crystalline phase Zr0.82Y0.18O1.91 at low heat-treatment temperatures. The precipitation of Zr0.82Y0.18O1.91 nanocrystals improves the Vickers hardness (5.17 GPa–5.56 GPa) and indentation fracture toughness (0.90 MPam1/2 to 1.01 MPam1/2) in glass-ceramics, while concurrently preserving a high level of visible light transmittance (∼90 %). This demonstrates its potential applications in the field of protective covers for electronic displays.

Effect of heat treatment on the microstructure and recrystallization of an SLM nickel-based superalloy

Heat treatment is essential for selective laser melting (SLM) of nickel-based superalloys. However, the conventional solution heat treatment method of cast superalloys usually leads to serious recrystallization in the samples. The recrystallized grain boundaries under high-temperature conditions reduce the strength of the alloy, which hinders their widespread applications in aerospace. In this work, a nickel-based superalloy with high γ′ content fabricated by SLM was heat-treated at different solution temperatures. The microstructure of the alloy in different heat-treated states was also characterised. A sub-solvus heat treatment was proposed, which can effectively reduce residual stress and inhibit recrystallization. The microstructure showed that the dislocation density was significantly reduced and recrystallized after the solution heat treatment at 1285 ℃/2 h+1290 ℃/2 h+1295 ℃/4 h and 1250 ℃/0.5 h, and the proportion of recrystallization were 60.0 % and 42.9 %, respectively. However, after sub-solvus heat treatment at 1240 °C/0.5 h, the sample dislocation density decreased and the volume fraction of recrystallization (3.2 %) was slightly higher than that of the as-SLM sample (2.5 %). The sample maintained a strong cubic texture in the build direction. After sub-solvus + aging heat treatment, the microstructure maintained a columnar grain structure. The γ/γ′ interfacial dislocation networks and dislocations pile-up were the main dislocation configurations.

Mechanical Properties and Microstructural Evolution of 6082 Aluminum Alloy with Different Heat Treatment Methods

The influence of solid solution treatment (SST), artificial aging treatment (AAT), and deep cryogenic-aging treatment (DCAT) on the mechanical properties and microstructure evolution of 6082 aluminum alloy was investigated. The tensile test was performed to obtain the true stress–strain curves through an electronic universal testing machine. The results show that the yield strengths of the SST specimens in all three directions are the lowest, of less than 200 MPa. In addition, the maximum elongation of the SST specimen is over 16% and the value of in-plane anisotropy (IPA) is 5.40%. For the AAT specimen, the yield strengths of the AAT alloy in three directions have distinct improvements, which are beyond 340 MPa. However, the maximum elongation and the IPA were evidently reduced. The yield strength and elongation of the DCAT alloy exhibit a slight enhancement compared with those in the AAT condition, and the corresponding IPA is 0.61%. The studied alloy specimens in all conditions exhibit ductile fracture. The DCAT alloy has the highest density of precipitates with the smallest size. Therefore, the dislocation pinning effect of the DCAT specimens are the strongest, which exhibit the highest yield strength accordingly. In addition, the uniformly distributed precipitates in the matrix with a large ratio of long and short axes can suppress the anisotropy caused by elongated grains.

SAVING ENERGY RESOURCES DURING THE HEAT TREATMENT OF CONCRETE DUE TO THE USE OF ADDITIVES

Purpose of the work is heat treatment (steaming) of concrete and reinforced concrete products as an effective method of accelerating concrete hardening. Heat treatment of concrete is one of the most responsible construction processes. There are known cases when, due to the increased temperature of the concrete and large temperature differences, excessive temperature stresses arose, as a result of which cracks were formed. When choosing a method of heat treatment of concrete, you must first consider the possibility of using an energy saving method. Its extension is the introduction of additives – concrete hardening accelerators and cements of increased heat release (fast-acting and high-quality), as well as plasticizers and superplasticizers. Methodology. To reduce the duration of heat treatment or reduce the temperature of isothermal heating, it is proposed to use an additive obtained on the basis of the sludge of metal processing enterprises. The work uses standard research methods to determine the physical and mechanical properties of reinforced concrete and the quality of complex additives in accordance with DSTU 9208:2022, DSTU B V. 2.7-2.7-114-2002, DSTU B V.2.7-215:2009, DSTU B V. 2.7-214:2009. Findings. The effect of a complex slurry-based additive on the properties of reinforced concrete was investigated. The proposed additive increases the strength of concrete in all accepted heat treatment modes compared to the strength of concrete without such an additive. Originality of the obtained results is the following, theoretically substantiated and experimentally confirmed complex additive to concrete based on sludge (cake) of metal processing enterprises. The effect of the additive on the strength characteristics of concrete subjected to heat treatment under different regimes and natural hardening concrete is shown. Practical value. The results of the work are implemented in the production of reinforced concrete products and structures.

Optimizing Heat Exchanger Cleaning in the Confectionery Industry: A Comparative Analysis of Ultrasonic, Heat Treatment, and Chemical Methods

Optimizing Heat Exchanger Cleaning in the Confectionery Industry: A Comparative Analysis of Ultrasonic, Heat Treatment, and Chemical Methods

Effects of Cr2O3 doping on crystallization behavior and electrochemical properties of Li2O–Al2O3–TiO2–P2O5–SiO2 glass-ceramics

Bulk glass-ceramic solid electrolytes of the Li2O–Al2O3–TiO2–P2O5–SiO2 system were prepared by melt-quenching and one-step heat treatment method in this work. The effects of the gradual substitution of Al3+ by Cr3+ and the elevation of the heat treatment temperature on the phase composition, microstructure, and ionic conductivity of the solid electrolytes were systematically investigated. The results show that the major crystalline phase is LiTi2(PO4)3, and the conductivity of the glass-ceramics initially enhances and then decreases as the Cr2O3 content increases from 0 mol% to 3 mol%. The highest conductivity is obtained when the Cr2O3 content is 2 mol%, measuring 4.45 × 10−4 S/cm at 25 °C. Additionally, the mechanism of the surface exfoliation of the glass-ceramics and the enhancement achieved by doping with Cr3+ are explained according to microstructure analysis. This work provides a simple method to enhance the electrical conductivity and physical properties of LATP glass-ceramic solid electrolytes, which is of great significance for the design of lithium-ion solid electrolytes.

Effect of post-weld heat treatment methods on microstructure and fatigue behavior of Al-Mg-Si alloy oscillating laser welding

To address the softening issue in aluminum alloy weld joints, post-weld heat treatment(PWHT) techniques were employed to enhance the mechanical properties of Al-Mg-Si alloy weld joints joined by oscillating laser welding(OLW). A systematic investigation was conducted on the impact of two different PWHT methods, artificial aging(AA) and solution treatment followed by aging(STA), on the static mechanical properties, fatigue performance, and microstructure of the weld joints. The results indicated that both AA and STA could improve the tensile strength and fracture strain of the welded joints. Compared to AA, STA did not show a significant improvement in increasing tensile strength and elongation at break. Notably, AA significantly increases the fatigue life of the joints, while STA also contributes to enhanced fatigue life, albeit to a lesser degree. At the lowest stress level, the fatigue life of both STA and as-welded(AW) joints exceeded 106 cycles, with the STA joints exhibiting approximately 57.9% higher fatigue life than the AW joints. Microstructural analysis of the AW joints revealed the presence of dislocations and a few large-sized precipitate phases, primarily Mg2Si and AlFeSi phases. After AA, nano-scale second phases, mainly the AlFeSi phase, appeared in the weld joints, accompanied by a reduction in dislocation density. Following STA, there was a significant increase in the density and size of precipitate phases, with the coarse AlFeSi phase becoming more prominent and large-sized grain boundary precipitates appearing. The AA treatment, due to grain refinement and second phase precipitation, enhanced the hardness, tensile strength, and fatigue strength of the joints. As the STA joints exhibited more β-AlFeSi precipitates and grain boundary precipitates, the second phase strengthening effect was reduced. Although the mechanical properties of STA joints were better than those of AW joints, they were inferior to those of AA joints.

Large-scale soil application of hydrochar: Reducing its polycyclic aromatic hydrocarbon content and toxicity by heating

The beneficial roles of hydrochar in carbon sequestration and soil improvement are widely accepted. Despite few available reports regarding polycyclic aromatic hydrocarbons (PAHs) generated during preparation, their potential negative impacts on ecosystems remain a concern. A heating treatment method was employed in this study for rapidly removing PAHs and reducing the toxicity of corn stover-based hydrochar (CHC). The result showed total PAHs content (∑PAH) decreased and then sharply increased within the temperature range from 150 °C to 400 °C. The ∑PAH and related toxicity in CHC decreased by more than 80% under 200 °C heating temperature, compared with those in the untreated sample, representing the lowest microbial toxicity. Benzo(a)pyrene produced a significant influence on the ecological toxicity of the hydrochar among the 16 types of PAHs. The impact of thermal treatment on the composition, content, and toxicity of PAHs was significantly influenced by the adsorption, migration, and desorption of PAHs within hydrochar pores, as well as the disintegration and aggregation of large molecular polymers. The combination of hydrochar with carbonized waste heat and exhaust gas collection could be a promising method to efficiently and affordably reduce hydrochar ecological toxicity.

Preparation of Binary and Ternary Laves and µ-Phases in the Ta–Fe(–Al) System for Property Analysis at the Microscale

Topologically close-packed (TCP) intermetallic phases are attractive candidates for adapting the property profile of both structural and functional materials, but their mechanical behavior, in particular below their brittle-to-ductile transition, is generally still poorly understood. The systematic analysis of the underlying deformation mechanisms requires the fabrication of homogeneous samples with sufficiently high purity and large enough grain size. Here, we describe identified pathways on the example of Laves and µ-phases from the binary Ta–Fe and ternary Ta–Fe–Al systems with regard to input materials, liquid metallurgy synthesis, heat treatment, and metallographic preparation methods. Preparation routes for structural analysis by electron backscatter diffraction and mechanical analysis by nanomechanical testing, as well as the transferability of our approach to other alloy systems containing TCP phases, are outlined and discussed.

REVIEW OF MODERN TECHNOLOGIES FOR INACTIVATION OF ANTI-NUTRIENTS IN SOYBEANS

The study examines technologies for inactivating anti-nutrients in soybeans, such as proteolytic enzyme inhibitors. In addition, soybeans have two trypsin inhibitors that bind cystine and methionine. Protease inhibitors include trypsin and chymotrypsin inhibitors, which are substances that are naturally present in soybeans to protect them from being eaten by birds and rodents and from the development of microflora. According to their heat resistance, antinutrients can be classified into heat-sensitive and heat-resistant. The purpose of the research was to study modern methods and technological solutions aimed at optimizing the preservation of useful characteristics of soybeans and reducing the content of anti-nutrients. To inactivate these anti-nutrients, physical, chemical and biological methods of legume processing are used. As a result of heat treatment, the nutritional value of beans increases, namely, the digestibility of proteins increases by up to 90%, and the contamination of beans with microflora is significantly reduced. The amount of trypsin inhibitor in soybeans after roasting with a roaster significantly decreased by 2.45 times, and lipoxygenase activity - by 2.71 times. One of the most attractive and highly effective, but not sufficiently researched methods is the method of heat treatment of legume seeds called micronization. In this case, the process of inactivation of anti-nutrients in soybeans is very fast - within 50...70 seconds, the nutritional value of protein is significantly increased, and the energy value increases (approximately from 7800 to 16000 kJ/kg). The technology of neutralization of anti-nutrients in soybeans based on their heat treatment in a 2.5 % solution of calcium hydroxide is considered. Processing of soybeans according to the developed technology allows to obtain feed without urease activity, and the content of trypsin inhibitor is at the level of 2-3 mg/g.

4D printing and annealing of PETG composites reinforced with short carbon fibers

In this study, for the first time, post-heat treatment was applied to improve the stress recovery of short carbon fiber reinforced PETG (SCFRPETG). PETG and SCFRPETG composite were printed under optimal conditions, and constrained and free shape memory cycles were applied under compression and three-point bending loadings to assess shape and stress recovery. The results of the free shape memory test for both vertical and horizontal patterns showed that PETG composite also has a higher shape memory effect (SME) compared to PETG. The SME was significantly improved by performing heat treatment. The stress recovery values for pure PETG, reinforced PETG before and after annealing are 2.48 MPa, 3.04 MPa and 3.18 MPa, respectively. It showed that the addition of 1.5% carbon fiber increases the stress recovery by 22%. The increasing trend reaches 28% by performing post-heat treatment. Additionally, altering the printing pattern affects the programming and stress recovery values. For the SCFRPETG composite samples before and after annealing, changing the printing pattern from horizontal to vertical, resulted in a 16% and 7% increase in recovery stress, respectively. SEM results confirm that the annealing process removes the layered structure, micro-holes caused by shrinkage and 4D printing mechanism. Using the controlled heat treatment method can be a practical solution to solve the problem of adhesion and reduce the anisotropy of FDM 3D printed layers.