Abrasive Blasting Process Research Articles

Effect of Organic Powders on Surface Quality in Abrasive Blasting Process

Abrasive blasting, sometimes known as sandblasting, is a method used to change the surface condition of materials, clean surfaces, and prepare surfaces for applications such as paint, bonding, coating, etc. The abrasive materials used in abrasive blasting are applied to the surface with compressed air or water and vary according to the purpose of application. The abrasive materials used have negative effects on the environment and human health. So far, organic materials have been used in limited applications in abrasive blasting. However, these materials have a high potential of usage since they are environmentally friendly, safe for human health, and have non-toxic and sustainable properties. In this study, the usability of three different organic wastes (walnut shell, olive pomace and mussel shell) recovered by recycling in abrasive blasting was investigated. In addition, the effect of blasting distance (5, 10 and 15 mm), blasting time (10, 20 and 30 s), powder type (mussel shell, olive pomace and walnut shell) and grain size (38, 45 and 63 µm) on surface roughness have been investigated using the Taguchi L9 experimental design. Regression models were built using ANOVA (Analysis of Variance). Moreover, the surface condition after abrasive blasting was examined using an Al2O3 abrasive and compared with other samples. As a result, 5 mm, 30 s, mussel shell and 45 µm test sets were recommended for “larger is better” and it was determined that the blasting time had the greatest effect on the surface roughness by 50.19%. On the other hand, 10 mm, 20 s, walnut shell and 63 µm test sets were recommended for “smaller is better”, and it was determined that blasting time had the greatest effect on the surface roughness by 39.02%. While there was an increase compared to the surface roughness values before abrasive blasting in the first set of experiments, it was determined that the organic material had a polishing rather than an abrasion effect in the second set of experiments.

Grain erosion wear properties and grinding performance of porous aggregated cubic boron nitride abrasive wheels

Cubic boron nitride (cBN) superabrasive grinding wheels exhibit unique advantages in the grinding of difficult-to-cut materials with high strength and toughness, such as titanium alloys and superalloys. However, grinding with multilayered metallic cBN superabrasive wheels faces problems in terms of grain wear resistance, the chip storage capability of the working layers and the stability and controllability of the dressing process. Therefore, in this work, novel metallic cBN superabrasive wheels with aggregated cBN (AcBN) grains and open pore structures were fabricated to improve machining efficiency and surface quality. Prior to the grinding trials, the air-borne abrasive blasting process was conducted and the abrasive blasting parameters were optimized in view of wear properties of cBN grains and metallic matrix materials. Subsequently, the comparative experiments were performed and then the variations in grinding force and force ratio, grinding temperature, tool wear morphology and ground surface quality of the multilayered AcBN grinding wheels were investigated during machining Ti–6Al–4V alloys. In consideration of the variations of grain erosion wear volume and material removal rate per unit of pure metallic matrix materials as the abrasive blasting parameters changes, the optimal abrasive blasting parameters were identified as the SiC abrasive mesh size of 60# and the abrasive blasting distance and time of 60 mm and 15 s, respectively. The as-developed AcBN grains exhibited better fracture toughness and impact resistance than monocrystalline cBN (McBN) grains because of the existence of metal-bonded materials amongst multiple cBN particles that decreased crack propagation inside whole grains. The metallic porous AcBN wheels had lower grinding forces and temperature and better ground surface quality than vitrified McBN wheels due to the constant layer-by-layer exposure of cBN particles in the working layer of AcBN wheels.

Toxicity studies of abrasive blasting agents administered by inhalation to F344/NTac rats and Sprague Dawley (Hsd:Sprague Dawley SD) Rats.

Abrasive blasting, commonly known as sandblasting, involves forcibly projecting a stream of abrasive particles through compressed air or steam against a surface to change its quality or to remove contaminants. Silica blasting sand contains high levels of crystalline silica--which can cause pulmonary fibrosis (silicosis) after exposure through inhalation and is considered a lung carcinogen--and constitutes approximately 63% of all abrasives used in abrasive blasting. Other abrasives, including specular hematite, are recommended as alternative blasting agents. Due to the health risks associated with using blasting sand in the abrasive blasting process and the lack of toxicity data on alternatives to blasting sand, the National Institute for Occupational Safety and Health (NIOSH) proposed testing blasting sand and alternative abrasives to characterize their associated toxicity. (Abstract Abridged).

The Condition of Ni-Cr Alloy Surface After Abrasive Blasting with Various Parameters

The parameters of abrasive blasting process directly affect the condition of the metal surface, changing the degree of surface roughness and wettability, depending on the size of the used particle, the pressure or type of abrasive. The aim of this study was to analyze the condition of Ni-Cr alloy surface after abrasive blasting using various process variants. The samples were blasted by Al2O3 abrasive using various particle sizes and pressures of the process. Basic and specific roughness parameters were investigated, and a surface wettability test was performed, and the percentage share of abrasive particles penetrated in the surface after abrasive blasting was also examined. The most considerable differences in the condition of the surface were observed with the change in the particle size of Al2O3. Statistical analysis confirmed the statistical significance of all these relationships.

Lung Function Test among Abrasive Blasting Workers in Lumut, Perak

Abrasive blasting process is a common process in marine industry. This process was use as main cleaning process method and normally will release fine dust that hazardous to human health. Main effect from fine dust to human health are respiratory failure such as chronic obstructive pulmonary disease (COPD). Lung function test can be used to detect any respiratory problems in human. The objective of the research to evaluate the effect of dust exposure from abrasive blasting to the workers. This study are conduct among workers work in dusty environment in Lumut, Perak, Malaysia. FEV1/FVC value from lung function test were evaluated to determine the severity of COPD among workers. While FEV1 prediction show restrictive pattern and use to determine any respiratory or lung problems among the workers. From the result, it does not show any COPD problem among workers. However, FEV1 show that some workers need to go for detail medical surveillance because of the result is less than 0.8. Employer and workers need to understand and know their work related risk to minimize the risk arising from their job or work conducted.

Automatic abrasive blasting system for large diameter pipe bends

Abrasive blasting is an important surface treatment process. Aiming at overcoming the shortage of the manual abrasive blasting process for large diameter pipe bends, T-pipes and gas collecting tubes, this paper presents the study of automatic abrasive blasting for large diameter pipe bends. According to the requirement of blasting process of large diameter pipe bend, the 5-DOF orthogonal coordinate abrasive blasting mechanism is constructed. Due to the massive dust and serious wear, the seal and protective measures of the mechanism are fully considered. In order to maintain a reliable operation of abrasive blasting system in severe environment, an automatic control system based on PLC is designed. In order to keep a specific angle between the sand-blasting gun and the workpiece surface, which can improve the working efficiency, the surface tracking control model was constructed based on the infrared distance measuring sensors. In order to improve the measurement accuracy of the sensors, the second order linear fitting method based on the least square method was used to calibrate the infrared range sensors. The experimental results indicate that the proposed automatic abrasive blasting system has significance on improving sand blasting quality, working efficiency and environment as well as reducing labour costs.

Automatic abrasive blasting system for large diameter pipe bends

Abrasive blasting is an important surface treatment process. Aiming at overcoming the shortage of the manual abrasive blasting process for large diameter pipe bends, T-pipes and gas collecting tubes, this paper presents the study of automatic abrasive blasting for large diameter pipe bends. According to the requirement of blasting process of large diameter pipe bend, the 5-DOF orthogonal coordinate abrasive blasting mechanism is constructed. Due to the massive dust and serious wear, the seal and protective measures of the mechanism are fully considered. In order to maintain a reliable operation of abrasive blasting system in severe environment, an automatic control system based on PLC is designed. In order to keep a specific angle between the sand-blasting gun and the workpiece surface, which can improve the working efficiency, the surface tracking control model was constructed based on the infrared distance measuring sensors. In order to improve the measurement accuracy of the sensors, the second order linear fitting method based on the least square method was used to calibrate the infrared range sensors. The experimental results indicate that the proposed automatic abrasive blasting system has significance on improving sand blasting quality, working efficiency and environment as well as reducing labour costs.

Laser surface pre-treatment of aluminum for hybrid joints with glass fiber reinforced thermoplastics

Lightweight construction is a major trend in the automotive industry. The connection of fiber reinforced plastics with aluminum is consequently seen as a promising prospect. In this regard, thermal joining is one potential joining technology for bonding of such hybrid joints. Yet a pretreatment of the aluminum surface is necessary to create a load bearing metal-plastic joint. Recent research has shown that a laser surface pretreatment provides high joint strengths. However, there is a variety of laser sources and possible surface topographies with typical structure sizes ranging from macroscopic to nanoscopic profiles. Within this work, two different laser induced structures were generated on aluminum sheets which were subsequently joined to glass fiber reinforced thermoplastics. One of the two laser structures was created with a continuous wave laser using a modified remote ablation cutting process. The other structure was manufactured by a pulsed laser source with a pulse width in the nanosecond-range. The two laser processes were compared with a conventional abrasive blasting process and they were characterized in terms of surface topography and chemical composition of the surface. Furthermore, the achievable joint strength for joining with glass fiber reinforced thermoplastics was investigated. It is shown that the properties of the thermoplastic as well as the surface topography and chemical composition of the metal strongly influence the resulting joint strength.

A novel abrasive blasting process: Abrasive medium classification and CFD simulations

AbstractThis study concerns the determination of the significant factors for an innovative deburring process: low pressure abrasive water‐jet blasting. The abrasive medium aluminum oxide (Al2O3) is classified according to the individual characteristics of different grain sizes. Then, the particle behavior in the air jet is analyzed with an optical measuring method, Particle Image Velocimetry (PIV); the velocity profile and the particle distribution of the dispersed system are obtained. Computational Fluid Dynamics (CFD) simulations were verified by comparing the experimental and numerical results, and the velocity range for the abrasive particles has been specified.

Improvement of wear resistant thermally sprayed coatings by microfinishing

To increase the wear resistance of tribologically highly stressed slide faces, thermally sprayed coatings based on tungsten carbide are widely used. In addition to the technological progress in powder metallurgy and coating technology, an improved preparation of the substrate surface increases the fatigue resistance of the coated workpieces. Surfaces machined by short-stroke honing instead of the commonly used abrasive blasting process, show a significantly enhanced interface between the surface and the coating. In addition, the use of diamond as hard cutting material enables the wear resistant coating to be honed and a high surface quality to be generated.

A wet abrasive blasting process for smooth micromachining of glass by ductile-mode removal

This paper describes the ductile removal behavior of a Pyrex glass substrate in a wet blasting process with an aqueous fine abrasive slurry of 4 µm Al2O3 particles in water. Glass was removed in a ductile cutting mode when the blasting was carried out with low applied pressure or with a long nozzle distance. Although the removal rate in the ductile mode was much lower than with brittle-mode blasting, a smooth surface within a roughness of 50 nm Ra was obtained. Using ductile-mode blasting, a micro groove with a smooth surface (roughness <50 nm Ra) was successfully obtained. The profile of the micro groove was U-shaped, in contrast to the V-shaped profile obtained with conventional brittle-mode blasting. Ductile-mode blasting was also used for surface finishing after a rough pre-blasting process. The roughness of the pre-blasted surface was reduced from 200 nm Ra to about 100 nm Ra by the finishing process.

Modelling and evaluation of the micro abrasive blasting process

Micro abrasive blasting (MAB) is becoming an important machining technique for the cost effective fabrication of micro devices. The material removal process is based on the erosion of a mask-protected brittle substrate by an abrasive-laden air jet. To exploit the potentials of this technique for applications of industrial interest, the blasting process has to become more efficient and better predictable. Therefore, in this paper micro-abrasive blasting is analysed by means of a set of models containing different sub-models for the particle jet, the erosion mechanisms of a single particle impact and the machining results. A one-dimensional isentropic flow model was developed to calculate the particle exit velocity of each individual particle in the airflow for two different types of nozzles: a converging cylindrical and a new developed line shaped Laval-type. The particle size and its position within the air jet are based on probability distribution functions. The result is a nozzles characteristic energy intensity distribution of the particle beam. Subsequently, classical indentation fracture mechanics is used to model the interaction between incoming particles and the substrate surface. The simulation shows that the Laval-type nozzle is able to increase the particle velocity with more than 30% compared to the converging nozzle. Also the blasting profile is more uniform with a relatively flat bottom. Experimental verifications of the particle velocities using particle image velocimetry (PIV) and measurements of the roughness and the shape of the blasting profile demonstrate that the presented model is capable to predict accurately the blasting performance of both nozzles types.

Simulation and Improvement of the Micro Abrasive Blasting Process

Micro abrasive blasting (MAB) is becoming an important machining technique for the fabrication of Micro Electro Mechanical systems. The process is based on the erosion of a mask-protected brittle substrate by an abrasive-laden air jet. Currently available blasting machines are relatively simple. However, to exploit this technique for applications of industrial interest a more efficient and controllable process is required. In this paper abrasive blasting is analysed by means of a set of models containing different sub-models for the particle beam, the material removal mechanism and the resulting blasting profile. A new line-shaped Laval nozzle has been developed, which is able to increase the particle velocity by 40% compared to a conventional round nozzle. The blasting-profile of this line-shaped nozzle is more uniform and the material removal rate is significantly higher compared to conventional nozzles, which in turn leads to higher achievable aspect ratios of the three-dimensional microstructures.

Metal cleaning and finishing by the airless abrasive blasting process

Metal cleaning and finishing by the airless abrasive blasting process