Residual Plastic Research Articles

Finite element analysis of chip formation usingale method

In recent times, many studies made in FEM on plain isotropic metal plate formulation. The stress analysis plays the significant role in the stability of structural safety and system. The stress and distortion estimation is very helpful for designing and manufacturing product well. Usually the residual stress and plastic strain determine the fatigue life of structure, it also plays the significant role in designing and choosing material. When the load magnitude increases the crack starts to form, decreasing the work load and the residual stress reduces the damage of the metal. The manufacturing process is a key parameter in process and forming the part of any system. However, machining operation involves complex thing like hot development, material property and other estimates based on transition of the plastic strain and residual stress. The reduction of residual stress plays the complexity role in the finite element study. This paper deals with the manufacturing process with less residual stress and strain. The results shows that, by applying the ALE method in machining we can reduce the load on the work piece hence the life type of the work piece can be increased. We also investigate the cutting tool wear and there efficiency since it is a essential machine member in fabrication technology. ABAQUS platform used to solve the machining operation

Analysis of Mullins effect in polyethylene using ultrasonic guided waves

Abstarct Small strain deformations below yielding can cause plastic deformation in semicrystalline polymers by a process similar to what is described for filled rubber-like materials known as the Mullins effect. Inter-lamellae chains contribute predominantly in deformations at this level, and the residual plastic strain can be attributed to permanent damage to the tie chains, affecting the long-term mechanical resistance of a molded part. With little detectable alteration of the polymer crystallinity at this early onset of plastic deformation, the primary characterization method applied to date is cyclic tensile loading, which provides information of stress-softening by monitoring the unloading path or relaxed stress behavior. An alternative method for monitoring the development of Mullins effect is proposed that can examine a molded part by using selected modes based on ultrasonic guided waves analysis. The technique was examined to determine if it could follow this effect induced by cyclic strain-controlled tensile deformations since it does not require sample preparation and could ultimately be applied while a part was in-service. Results for different polyethylene grades agree in trend with relaxed stress values over four cycles for tests of increasing applied tensile strain, demonstrated by an increase in the attenuation of ultrasonic guided waves. The correlation reveals a good promise in applying this method to structural health monitoring of plastic parts, while in use, to follow the initiation and progress of early service damage.

Lightweight expanded aggregates from the mixture of waste automotive plastics and clay

Significant amount of waste associated with end of life vehicles enter waste stream each year and are usually disposed of in landfill, creating an environmental burden. Recycling automotive waste is very tedious and difficult due to its heterogeneous composition and nature. It is critically required to develop a solution to recycle and reuse these potential resources. In this paper, a novel recycling approach is established to produce lightweight aggregate by incorporating automotive shredded residual (ASR) plastics into clay at 1200°C. The physical properties of lightweight aggregate such as bulk density, porosity and water absorption have been investigated. ASR plastics as pore-forming or gas releasing agent increased the porosity of the clay mixture. Incorporation of 2wt% of ASR plastics into clay composite lead to a benefit of approximately 30% bulk density decrease and 40% porosity increase compared to the reference clay material used in this study. The obtained superior lightweight and porous aggregate products by using ASR plastics can be used in thermal insulation materials and also as substrates in soilless cultivation. This innovative approach could also help reduce the volume of autoplastics in landfills and could be a potential replacement of conventional additives in manufacturing composite materials for building applications.

Numerical simulation and experiment analysis of angular distortion and residual stress in hybrid laser-magnetic welding

Hybrid laser-magnetic welding 316L steel with butt joint was investigated. The bottom width of the bead profile was broadened from 1.606mm to 2.492mm, grain size was homogenized, and austenitic content was also improved. Considering the influence of magnetic field on bead geometry, a new simplified heat source model was developed and used to simulate temperature distribution. Integrating the steady magnetic field with laser welding, angular distortion was reduced by 26.56%, the longitudinal residual stress was smoothed, transverse tensile stress was cut down from 199.1MPa to 167.3MPa, longitudinal residual plastic strain (−0.009) was homogenized to −0.007, and transverse residual plastic strain was decreased from −0.08 to −0.075. The laser-magnetic welding was useful to homogenize the weld of bead geometry, microstructure, angular distortion, residual stress and plastic strain.

Experimental Study on the Dilatancy and Fracturing Behavior of Soft Rock Under Unloading Conditions

To reveal the deformation mechanism during tunneling in deep soft ground, triaxial unloading confining pressure tests and triaxial unloading creep tests were carried out on sandy mudstone specimens to study the dilatancy and fracturing behavior of soft rock. In the triaxial unloading confining pressure tests, the stress path and different unloading rates were considered to reflect the unloading characteristics of the excavation methods. The unloading rate effects and the rock damage evolution law are studied. The following conclusions are obtained from the results. Firstly, when the unloading rate is smooth, the peak strengths and deviatoric stress–strain curves under the unloading condition are close to those under the conventional loading condition. Secondly, the post-peak brittle characteristics are more apparent with the increasing unloading rates. Thirdly, the soft rock undergoes five deformation and failure regimes of elasticity, pre-peak unloading damage–dilatancy, post-peak brittle drop, linear strain softening and residual perfect plasticity under quasi-static smooth unloading of mechanized excavation which is mainly focused on in this study. Fourthly, the damage evolution law at the pre-peak damage–dilatancy stage follows an exponential function. Fifthly, during the post-peak stages, multistage microfractures are initiated, propagated and finally coalesced forming a shear-fragmentation band with a certain thickness, accompanied by significant volumetric dilatancy. In the triaxial unloading creep tests, multistep unloading of the confining pressure was applied, while the axial pressure was kept constant. The results show that when the deviatoric stress is larger and the experienced creep time is longer, the unloading effect and creep characteristics become more apparent accompanied with obvious lateral dilatancy, eventually leading to significant creep–dilatancy. The progressive failure with time is caused by the damage accumulating with time-dependent crack expansion, which can be called as ‘time-dependent damage and fracturing’. The reasons for the above evolution process are presented, then the deformation mechanism of soft rock is revealed. The soft rock deformation mainly consists of two parts. One part is the pre-peak damage–dilatancy and post-peak fracture–bulking produced at the excavation unloading instant. The other part is creep–dilatancy caused by time-dependent damage and fracturing in a period of time after excavation. The above-mentioned results of damage, dilatancy and fractures evolution process are in good agreement with the in situ monitoring results and previous studies about the surrounding rock convergence, fracturing and EDZ (excavation damaged zone) development.

Investigation on effect of grain orientation in photochemical machining of Monel 400

ABSTRACTIn this study, microchannels with widths of 60, 100, 150, 200, and 250 µm were fabricated on the surface of Monel 400 alloy, and the effect of the rolling direction on the surface finish and etching depth was investigated. The obtained results revealed that the quality of the microchannel surface finish was better along the rolling direction than across the rolling direction, owing to the grain boundary orientations along the (001) plane. In addition, the etching depth increased along the rolling direction due to the presence of residual stress and plastic strain, which ultimately improved the microchannel quality.

Determination of equi-biaxial residual stress and plastic properties in structural steel using instrumented indentation

This study describes a method that allows estimation of the equi-biaxial residual stress (σR), yield strength (σy), the strain hardening exponent (n), and the ratio (α) between strain at starting-point of strain hardening (εst) and yield strain (εy) of structural steel from the load-depth curve of one sharp indentation test. In this method, the relationships between the structural steel properties, residual stress, and the characteristics of the indentation loading-unloading curves were established in the form of dimensionless functions via extensive finite element (FE) analyses. Based on the FE analysis results of the indentation process with a large number of different material properties combinations, the effects of residual stress and plastic parameters on the indentation response were investigated, and a reverse algorithm for estimating four unknown quantities (σR, σy, n, and α) of steel from an indentation test was proposed. A stress-applying apparatus that allows the introduction of a compressive or tensile stress to the sample by applying a compressive or tensile force and maintaining the stress after releasing the force was also developed in this study. Indentation and tensile tests of structural steels (SS400 and SM490) were carried out and the proposed algorithm was validated through both numerical analyses and experimental results.

Numerical and Experimental Study on Cutting Access Opening in Ship Structure

Creating an access opening in ship structure through thermal cutting is an important process in ship repair and reconstruction. The flame cutting process typically leads to a nonuniform temperature distribution, generates residual thermal stress and localized plastic deformation. As openings are needed at various locations of ship hulls, it is also necessary to consider the effects of structural constraints in the immediate end of the plate where the plate is either welded or fixed to the ship frame or bulkhead. These are challenging tasks. This article presents a study based on the thermal elastoplastic analysis. By using the finite element techniques, a steel plate model undergoing flame cutting process to create an opening was studied in details. The numerical model was validated with experimental data. The study identified several key parameters that are 1) structural boundary condition, 2) steel plate size, 3) opening location, and 4) opening shape.

Comparison of mouse and human retinal morphology and function in albinism: potential implications for therapeutic development

BackgroundAlbinism is a disorder of melanin biosynthesis characterised by abnormal retinal development (foveal hypoplasia) and visual impairment, for which there are no effective treatments. Residual neural plasticity in the infant albino retina has previously been demonstrated. Therapeutic intervention during this developmental period has the potential to rescue visual function. Preclinical studies in murine albinism models are essential to develop novel therapeutics. We aimed to characterise retinal development, morphology, and function in the C57BL/6J-c2J null mouse model of oculocutaneous albinism (OCA), in preparation for future proof-of-concept treatment studies. MethodsWe obtained 53 mixed cross-sectional and longitudinal in-vivo optical coherence tomography (2·2 μm axial resolution; Bioptigen, Morrisville, NC, USA) and electroretinography (Micron III; Phoenix, Pleasanton, CA, USA) examinations from nine C57BL/6J-c2J OCA mice at 4, 5, 6, 8, 12, and 16 weeks of age, which were compared with 110 examinations from 11 C57Bl/6J control mice. Retinal layer segmentation was performed with InVivoVue Diver 2.4 software (Bioptigen). Linear mixed regression modelling was used to analyse group differences. The results were then compared with published data on human albino retinal development, morphology, and function. FindingsIn individuals with albinism, foveal hypoplasia is seen on optical coherence tomography, with the length of the photoreceptor outer segment correlating with visual acuity. Electroretingraphy responses are not affected. By contrast, although mice do not have foveae, we found significant reductions in the combined ganglion cell and inner plexiform layer (p=0·001) and retinal pigment epithelium (p<0·0001) thickness measurements, and also reductions in the length of the photoreceptor outer segment (p<0·0001) and end-tips (p=0·005) at 16 weeks of age in OCA mice. These findings corresponded with significant reductions in mean amplitudes on electroretingraphy in OCA mice compared with control mice (A-wave −98·3 μV [SD 62·9] vs −113 [66·5], p=0·028; B-wave 219·1 [90·1] vs 261·8 [98·9], p=0·003). InterpretationWe have identified several differences in using optical coherence tomography and electroretinography to monitor retinal morphology and function in human and mouse albinism. This finding is important for future translational studies and therapeutic development in albinism. FundingAcademy of Medical Sciences, Gift of Sight.

Influence of Strain on Current Densities and Stress Corrosion Cracking Growth Rates in X65 Pipeline Steel

High pH stress corrosion cracking (SCC) in gas pipelines has been seen to grow along an incline angle rather than perpendicular to the outer surface. Crack tip strain enhanced electrochemistry has been previously postulated as a reason for the inclination, and recent computer simulations that take this effect into account produce realistic crack paths. This study attempts to determine the effect of strain on the electrochemical response of X65 steel, and the impact that the strain has on growth rates for inclined SCC. Potentiodynamic tests were conducted on X65 tensile specimens with residual plastic strain or in situ elastic strain. An increase of the current density up to 300% was observed within the SCC potential range. Computer simulations were also conducted to show the qualitative effect of this increase in current density on the growth rate, and results indicated that inclined SCC could grow to 50% wall thickness faster than straight SCC if the current density along the inclined angle is 20% higher...

Mechanical and shape memory properties of porous Ni50.1Ti49.9 alloys manufactured by selective laser melting

Near equiatomic NiTi shape memory alloys were fabricated in dense and designed porous forms by Selective Laser Melting (SLM) and their mechanical and shape memory properties were systematically characterized. Particularly, the effects of pore morphology on their mechanical responses were investigated. Dense and porous NiTi alloys exhibited good shape memory effect with a recoverable strain of about 5% and functional stability after eight cycles of compression. The stiffness and residual plastic strain of porous NiTi were found to depend highly on the pore shape and the level of porosity. Since porous NiTi structures have lower elastic modulus and density than dense NiTi with still good shape memory properties, they are promising materials for lightweight structures, energy absorbers, and biomedical implants.

Dynamical approach to displacement jumps in nanoindentation experiments

The load-controlled mode is routinely used in nanoindentation experiments. Yet there are no simulations or models that predict the generic features of force-displacement F-z curves, in particular, the existence of several displacement jumps of decreasing magnitude. Here, we show that the recently developed dislocation dynamical model predicts all the generic features when the model is appropriately coupled to an equation defining the load rate. Since jumps in the indentation depth result from the plastic deformation occurring inside the sample, we devise a method for calculating this contribution by setting up a system of coupled nonlinear time evolution equations for the mobile and forest dislocation densities. The equations are then coupled to the force rate equation. We include nucleation, multiplication, and propagation threshold mechanisms for the mobile dislocations apart from other well known dislocation transformation mechanisms between the mobile and forest dislocations. The commonly used Berkovitch indenter is considered. The ability of the approach is illustrated by adopting experimental parameters such as the indentation rate, the geometrical quantities defining the Berkovitch indenter including the nominal tip radius, and other parameters. We identify specific dislocation mechanisms contributing to different regions of the F-z curve as a first step for obtaining a good fit to a given experimental F-z curve. This is done by studying the influence of the parameters on the model F-z curves. In addition, the study demonstrates that the model predicts all the generic features of nanoindentation such as the existence of an initial elastic branch followed by several displacement jumps of decreasing magnitude, and residual plasticity after unloading for a range of model parameter values. Further, an optimized set of parameter values can be easily determined that gives a good fit to the experimental force-displacement curve for Al single crystals of (110) orientation. The stress corresponding to the maximum force on the elastic branch is close to the theoretical yield stress. We also elucidate the ambiguity in defining the hardness at nanometer scales where the displacement jumps dominate. For larger indentation depths where displacement jumps disappear, the indentation size effect is predicted. The approach also provides insights into several open questions.

Welding distortion prediction based on local displacement in the weld plastic zone

For a welding procedure with grooves or filler materials, to avoid underestimating the welding distortion in predictions based on the residual plastic strain, a prediction approach is proposed to estimate the welding distortion based on the local displacement in the weld plastic zone, and the proposed method is verified using the thermal elastic–plastic finite element method. Additionally, the welding distortions of an orthotropic deck are estimated using the proposed method and compared with the experimental measurements. The results show that the proposed method can be used to predict the welding distortion with a high accuracy, and in addition to the welding procedures with grooves or filler materials, the proposed method is also applicable to procedures without them.

Sensory Eye Dominance in Treated Anisometropic Amblyopia.

Amblyopia results from inadequate visual experience during the critical period of visual development. Abnormal binocular interactions are believed to play a critical role in amblyopia. These binocular deficits can often be resolved, owing to the residual visual plasticity in amblyopes. In this study, we quantitatively measured the sensory eye dominance in treated anisometropic amblyopes to determine whether they had fully recovered. Fourteen treated anisometropic amblyopes with normal or corrected to normal visual acuity participated, and their sensory eye dominance was assessed by using a binocular phase combination paradigm. We found that the two eyes were unequal in binocular combination in most (11 out of 14) of our treated anisometropic amblyopes, but none of the controls. We concluded that the treated anisometropic amblyopes, even those with a normal range of visual acuity, exhibited abnormal binocular processing. Our results thus suggest that there is potential for improvement in treated anisometropic amblyopes that may further enhance their binocular visual functioning.

Dynamic numerical simulation of plastic deformation and residual stress in shot peening of aluminium alloy

Shot peening is a cold surface treatment employed to induce residual stress field in a metallic component beneficial for increasing its fatigue strength. The experimental investigation of parameters involved in shot peening process is very complex as well as costly. The most attractive alternative is the explicit dynamics finite element (FE) analysis capable of determining the shot peening process parameters subject to the selection of a proper material´s constitutive model and numerical technique. In this study, Ansys / LS-Dyna software was used to simulate the impact of steel shots of various sizes on an aluminium alloy plate described with strain rate dependent elasto-plastic material model. The impacts were carried out at various incident velocities. The influence of shot velocity and size on the plastic deformation, compressive residual stress and force-time response were investigated. The results exhibited that increasing the shot velocity and size resulted in an increase in plastic deformation of the aluminium target. However, a little effect of the shot velocity and size was observed on the magnitude of target´s subsurface compressive residual stress. The obtained results were close to the published ones, and the numerical models demonstrated the capability of the method to capture the pattern of residual stress and plastic deformation observed experimentally in aluminium alloys. The study can be quite helpful in determining and selecting the optimal shot peening parameters to achieve specific level of plastic deformation and compressive residual stress in the aluminium alloy parts especially compressor blades.

Dynamic Impact Induced Residential Stress and Deformation in Silicon Carbide Ceramics

Silicon carbide ceramics with different grain sizes were tested at high strain rate using a small-scale gas gun with sharpened tungsten carbide projectiles impacting at a sub-ballistic velocity of 100 m/s. The resistance of ceramics to fracture was recorded by visual examination of the cracking on the impacted surface and the damage in the sub-surface region. The crack pattern and impact crater region size observed in silicon carbide specimens are generally due to their mechanical properties. Silicon carbide samples had good capacity to defeat the projectiles but the low toughness led to early failure. Raman SiC mapping was used to examine the residual stress and plastic deformation induced in each material. The silicon carbide samples showed different dynamic behaviours due to the extent of stress relaxation.

生物降解地膜周年降解特性对北方灌区玉米增产机理研究

生物降解地膜是解决地膜残留污染问题的重要途径，对农业发展潜力巨大，但不同生物降解地膜对不同生态区域玉米生长的适配性各异，影响其推广应用。本文通过大田试验，从地膜田间降解特性、土壤保温性、作物生长发育、产量及其构成因子、残留地膜覆盖率等方面对9种可降解生物地膜与普通PE (CK1)地膜和露地栽培(CK2)进行了对比研究。结果表明：试验筛选出GS05、GS09、GS10和GS03四种生物可降解地膜，玉米生长前期降解缓慢，中期和后期降解较快，与玉米生长发育适配性较好；10 cm处土层地温在玉米全生育期、出苗至拔节期、抽雄至灌浆期分别比CK1降低0.1℃~0.5℃、0.5℃~1.0℃、0.2℃~ −0.5℃；成熟至收获期日较差提高了−0.9℃~0.6℃；出苗率、株高、茎粗、棒穗长、每棒穗粒数、千粒重分别比(CK1)提高了−3.3~3.4百分点、−16.7~−3.5 cm、−0.2~−0.3 cm、−2.7~0.0 cm、−33.7~−16.4粒、−17.3~−7.0 g；玉米产量12,664.5~14,493.0 kg/hm2，较CK1减产0.6%~13.1%，说明四种生物可降解地膜和普通地膜对玉米产量影响差异不大，较CK2增产86.3%~113.1%，产量差异达极显著水平。四种生物可降解地膜的覆盖率，玉米收获时分别为25.8%、64.3%、24.4%和51.5%，至翌年玉米播种时分别为3.3%、7.4%、6.2%和16.5%，说明四种生物可降解地膜的降解特性基本符合北方高海拔灌区玉米生长对环境的要求，完全可以替代传统地膜。 Biodegradable plastic film is an important way to solve the problem of plastic film residue pollu-tion. It has great potential for agricultural development, but different biodegradable plastic films were different in different ecological regions and affected its popularization and application. In this paper, comparative field experiments were carried out among three cultivation methods, 9 biodegradable films cultivation, ordinary PE (CK1) film cultivation and open field cultivation (CK2), from field degradability of plastic film, soil thermal insulation, crop growth, yield and its composition factors, residual plastic film coverage and so on. The result showed that the degradation of the selected four kinds of biodegradable plastic films GS05, GS09, GS10 and GS03 was slow at the early growth stage of maize and quicker in the middle and later stages, and the growth adaptability of maize was better. The soil temperature in the whole maize growth period at 10 cm soil layer from emergence to jointing stage, from tasseling to filling stage compared to CK1, decreased from 0.1˚C to 0.5˚C, from 0.5˚C to 1.0˚C and from 0.2˚C to 0.5˚C. The difference of maturity from harvest to maturity was improved by −0.9˚C - 0.6˚C. Emergence rate, plant height, stem diameter, panicle length, grain number perpanicle, 1000-grain weight compared to CK1 increased by −3.3 - 3.4 percentage points, −16.7 to −3.5 cm, −0.2 to −0.3 cm, −2.7 to 0.0 cm, −33.7 to −16.4, −17.3 to −7.0 g; maize yield was 12,664.5~14,493.0 kg/hm2, which was 0.6~13.1% less than that of CK1. The results showed that the effect of four biodegradable mulches and ordinary mulching film on maize yield was not significant, which was 86.3% - 113.1% higher than that of CK2, and the difference was significant. The coverage of the four kinds of biodegradable mulching films was 25.8%, 64.3%, 24.4% and 51.5% respectively when corn was harvested, which was 3.3%, 7.4%, 6.2% and 16.5%. These results indicated that the degradation characteristics of the four biodegradable plastic mulch basically accorded with the environmental requirements of maize growth in the high elevation irrigation area of northern China, and could replace the traditional mulching film.

Effect of Heating and Deformation on Properties of Highly Deformable Pipe Metal During Cold Bend Manufacture

The change in mechanical properties and shape parameters is studied for pipe with high deformation capacity (HDC) 1420 × 21.7 mm in size of strength class K60 during cold bend manufacture with a reduction in bend radius. Features are demonstrated of steel structure of HDC pipes providing ageing resistance and improved deformation capacity, including presence of MA component and polygonal ferrite in a bainitic matrix. The use of HDC pipes will make it possible to prepare bent sections with a radius reduced to R ≈ 20Do without corrugation formation and with geometric parameters within the framework of specifications for “standard” bends. Thermal action during application of an anticorrosion coating (200–250°C) leads to an increase in strength, especially σy(Rt0.5) and the ratio σy(Rt0.5)/σu in the longitudinal direction and reduction in ductility (δ5 and δu). However, after HDC pipe heating sufficient deformation capacity is obtained for bends. Features are determined for the change in mechanical properties and tensile curves for steel in zones subjected to tension (TZ) and compression (CZ) during pipe bending with residual plastic deformation up to ~3%. For TZ and CZ metal, there is a different direction of the change in σy and σy/σu in the longitudinal direction, and also a reduction in ductility indices (δ5 and δu) in transverse and longitudinal directions. The production limitations revealed during pipe bending arising due to the danger of jamming of a mandrel in a pipe during bending are revealed.

Residual stresses in shape memory alloy fiber reinforced aluminium matrix composite

Process-induced residual stress in shape memory alloy (SMA) fiber reinforced aluminum (Al) matrix composite was simulated by ANSYS APDL. The manufacturing process of the composite named as NiTi/Al is start with loading and unloading process of nickel titanium (NiTi) wire as SMA to generate a residual plastic strain. Then, this plastic deformed NiTi wire would be embedded into Al to become a composite. Lastly, the composite is heated form 289 K to 363 K and then cooled back to 300 K. Residual stress is generated in composite because of shape memory effect of NiTi and mismatch of thermal coefficient between NiTi wire and Al matrix of composite. ANSYS APDL has been used to simulate the distribution of residual stress and strain in this process. A sensitivity test has been done to determine the optimum number of nodes and elements used. Hence, the number of nodes and elements used are 15680 and 13680, respectively. Furthermore, the distribution of residual stress and strain of nickel fiber reinforced aluminium matrix composite (Ni/Al) and titanium fiber reinforced aluminium matrix composite (Ti/Al) under same simulation process also has been simulated by ANSYS APDL as comparison to NiTi/Al. The simulation results show that compressive residual stress is generated on Al matrix of Ni/Al, Ti/Al and NiTi/Al during heating and cooling process. Besides that, they also have similar trend of residual stress distribution but difference in term of value. For Ni/Al and Ti/Al, they are 0.4% difference on their maximum compressive residual stress at 363K. At same circumstance, NiTi/Al has higher residual stress value which is about 425% higher than Ni/Al and Ti/Al composite. This implies that shape memory effect of NiTi fiber reinforced in composite able to generated higher compressive residual stress in Al matrix, hence able to enhance tensile property of the composite.

Contact properties determination of macroscopic fine disperse glass particles via compression tests under cyclic loading/unloading

To investigate the permanent compressive stress of single particles in a cohesive bulk solid during handling or transport, uniaxial compression tests were carried out with cyclic loading/unloading. This involves a continuation of our previous studies (contact properties determination of macroscopic fine disperse glass particles via compression tests in normal direction). The experiments were implemented by means of a home-built compression tester. By repeated loading/unloading cycles with spherical, dry and smooth soda lime glass particles with a mean diameter of d50,3=513.20μm, a set of micromechanical contact properties was determined. It is a model-based back-calculation of experimentally generated normal force-displacement curves of the elastic-plastic sample material. For this purpose, the contact model ‘stiff particles with soft contacts’, which was developed by Tomas, is used. In order to influence the flowability of soda lime glass particles and to verify the effect of the characteristic adhesion force on the elastic-plastic contact, the particles were altered to be hydrophilic and hydrophobic.Finally, the effect of the number of cyclic loading/unloading tests on the contact stiffness, the effective modulus of elasticity and the resulting contact radius was explained and discussed. According to this, there is an increase of the elastic-plastic contact stiffness up to a saturation of the plastic deformation during the repeated loading of the contact with a constant load rate of FN,max=45N.The determined residual plastic deformations in cyclic compression tests are directly correlated to the densification in the contact area of soda lime glass particles due to the absent long-range order in the glass structure.