As two precise and efficient cutting processes, laser cutting and waterjet cutting are both widely used manufacturing technologies. Of course, there are significant differences between the two. If you want to choose the most suitable process for your manufacturing project, it is essential to understand these differences. In the following, I will provide a detailed comparison of these two technologies to help you better understand and evaluate them.
What Is Laser Cutting?
Laser cutting is a thermal cutting process that uses a high energy density beam (usually CO2 laser or fiber laser) focused on the material surface, and then cuts the material through melting, vaporizing, or burning. The temperature at the focal point can reach several thousand degrees Celsius, causing materials to rapidly melt or vaporize. During the cutting process, the laser beam’s trajectory is precisely controlled by a CNC system, and auxiliary gases (O₂, N₂, Ar) are used to blow the molten material away from the cut seam. Overall, the cutting efficiency is quite high.
Laser cutting is essentially a non-contact processing method, where the tool does not contact the workpiece, and there is no mechanical stress.
What Is Waterjet Cutting?
Waterjet cutting is a cold cutting process that uses a high-pressure water jet to strike the surface of a material at extremely high speeds, cutting through the material by erosion and shearing. The velocity of the water jet at the nozzle can reach 900 m/s. For some hard materials, you can also add abrasives to the water jet to increase its cutting ability. It should be noted that the waterjet cutting process can achieve precision cutting from thin plates to thick plates without generating a heat-affected zone.
Additionally, waterjet cutting is also a non-contact process. The cutting head is controlled by a CNC system to control the cutting path, enabling the cutting of complex contours.
Laser Cutting vs Waterjet Cutting: Performance
Next, I will provide a detailed comparison of the performance of these two processes.
Precision & Tolerances
Laser Cutting：
When you use laser cutting process to cut thin plates (<6mm), the tolerance can stably reach ±0.05mm, while when cutting thick plates (>12mm), the tolerance is usually controlled within the range of ±0.1mm–±0.2mm. Moreover, laser cutting has a very narrow kerf, so material utilization can reach 85%–95%. In addition, the HAZ width range of this process is 0.05mm–0.5mm, which can easily lead to localized hardening of the cut edges.
As for the surface roughness of the laser cutting process, the Ra value varies depending on the material and thickness. The range of the Ra value is generally between 0.8–3.2 μm.
Waterjet Cutting:
The standard cutting tolerance range for waterjet cutting process is ±0.1mm–±0.25mm, while in high precision mode, the tolerance range of this process can be controlled within ±0.05mm–±0.1mm.
Taper has always been a technical challenge in waterjet cutting. The abrasive jet gradually loses energy as it penetrates the material. Since the jet velocity is lower at the bottom of the cut than at the top, this results in a V-shaped or inverted V-shaped kerf profile. The thicker the material, the more pronounced the taper becomes.
Of course, there are solutions to this problem. You can choose to use a 5-axis cutting head to compensate for the taper by tilting the cutting head angle, or you can also reduce the cutting speed, which will make the jet’s capability more uniform.
Additionally, waterjet cutting processes do not have heat-affected zone issues, which means the cutting edge of the sheet material has exactly the same metallographic structure as the base material.
Speed & Productivity
In the field of thin-sheet cutting, the speed advantage of laser cutting is quite significant. Taking 3mm carbon steel as an example, the cutting speed of a 6kW fiber laser can reach 10–18 m/min, while under the same conditions, the speed of an abrasive waterjet is only 0.6–0.8 m/min, a difference of 15 to 25 times. Therefore, when the sheet thickness to be cut is less than 6 mm, laser cutting is undoubtedly the preferred process for high-volume applications such as sheet metal fabrication, electronic enclosures, and automotive stampings.
However, as the thickness of the sheet increases, the speed difference between the two will significantly narrow. When the thickness of the sheet exceeds 50mm, the edge quality of laser cutting begins to decline noticeably. For ultra-thick sheets exceeding 100 mm, waterjet cutting is virtually the only viable option.
In addition, piercing time is another factor that cannot be overlooked. Laser cutting achieves extremely fast piercing times on thin sheets, typically taking no more than 0.1 seconds. Waterjet cutting, on the other hand, requires the system to establish a stable ultra-high-pressure jet, which takes 3–8 seconds to pierce thin materials, and for thicker sheets, the time required is even longer.
Cutting Edge Quality
Laser cutting produces edges with a high degree of perpendicularity. The cut surfaces of thin sheets less than 6 mm thick are nearly perfectly perpendicular, with a taper angle of less than 0.5°. Furthermore, the direction of the striations is consistent.
Waterjet cutting produces a cold-cut surface with no heat-affected zone and no oxidation or discoloration. Additionally, the striations on the edge appear as curved, trailing lines.
Laser Cutting vs Waterjet Cutting: Cost Analysis
I’m sure cost is also a concern for you. Below, I’ll analyze the cost factors from two perspectives.
Equipment Cost
Laser cutting machines are divided into several tiers, with significant price differences between machines of different levels. For every increase in a machine’s power level, the price increases by 30%–80%. The price range is between $8,000 and $250,000. And the key factors affecting the equipment cost of laser cutting also include worktable size and the degree of automation of the equipment, etc.
The overall equipment cost for waterjet cutting is also divided into several ranges, with prices varying from $60,000 to $450,000. The factors that cause equipment price fluctuations are pump pressure levels, with high-pressure pumps costing approximately 50%–100% more. Additionally, there are factors such as equipment table size, number of axes, and number of cutting heads, etc.
Operating Cost
The operating costs of these two processes are also a significant factor in overall expenses.
| Cost Item | Laser Cutting | Waterjet Cutting | Notes |
| Electricity | Higher | Lower | High-power laser machines consume more electricity |
| Gas / Abrasive | Medium | High | High operating costs of waterjet abrasives |
| Consumables | Lower | Higher | High consumption of waterjet mixing tubes and nozzles |
| Maintenance | Lower | Higher | Laser has a clear advantage in maintenance cost |
| Labor | Low | Medium | Laser automation integration is more mature |
| Total per Hour | $10–$111 | $22–$90 | Varies significantly depending on power level and configuration |
Laser Cutting vs. Waterjet Cutting: Materials
Laser Cutting Materials
Laser cutting is suitable for a wide variety of materials, including both metals and non-metals.
Metal Materials
- Carbon Steel: The most mainstream material for laser cutting, with the highest maturity in the process.
- Stainless Steel: Laser cutting is excellent and is one of the most common materials.
- Aluminum Alloy: Cuttable. However, you must use nitrogen cutting to prevent oxidation
- Copper & Brass: Highly reflective materials. Additionally, brass is easier to cut than pure copper.
- Titanium alloy: This material can be processed, but the process parameters must be strictly controlled.
- Tool steel: This material can be processed, but significant hardening will occur in its heat-affected zone (HAZ).
Non-Metallic Materials
- Acrylic: Excellent laser cutting performance, one of the most ideal non-metallic cutting materials
- Wood: Good CO₂ laser cutting performance
- Rubber: Can be cut, but processing this material produces large amounts of toxic fumes
Waterjet Cutting Materials
Next are the materials suitable for waterjet cutting.
Metal Materials
- Carbon Steel: The water jet cutting effect is excellent, and there is no issue with oxidation layers.
- Stainless Steel: The waterjet cutting effect is outstanding, and there is no risk of sensitization.
- Aluminum Alloy: The waterjet cutting effect on aluminum alloys is excellent, and there will be no issues with reflection and thermal distortion.
- Copper & Brass: You can use waterjet cutting to cut copper alloys without any adverse effects.
- Superalloy: Waterjet cutting works very well on these materials.
Non-Metallic Materials
- Stone: The most mainstream non-metallic material, widely used in the construction industry
- Glass: Water jet cutting produces the best results for glass cutting
- CFRP: Water jet cutting of CFRP is the recommended process in the aerospace field
- Ceramics: Water jet can cut most engineering ceramics
Laser Cutting vs. Waterjet Cutting: Application
Although both of these processes are used for cutting, their specific applications differ. Below, I will explain them to you one by one.
Laser Cutting Applications
Automotive Parts
In the automotive industry, laser cutting is commonly used for processing automotive parts such as body structural components, metal brackets, exhaust system components, and interior metal parts. Because laser cutting is highly automated, this process is also suitable for rapid prototyping and mass production.
Mechanical Equipment Parts
In the mechanical industry, laser cutting is widely used in the production of base plates, connecting parts, protective covers, and metal frame structural components. This process is particularly suitable for manufacturing parts with high precision requirements in terms of dimensions, hole positions and edge quality.
Sheet Metal Fabrication
Laser cutting is ideal for processing thin and medium-gauge metal sheets, particularly materials such as stainless steel and aluminum alloys. You use this process to produce sheet metal processing parts with high-precision contours, holes, and slots. In addition, this process ensures excellent dimensional consistency for mass-produced parts.
Electronics
Laser cutting can be used to process electrical components such as control panel enclosures, heat sinks, metal shielding covers, and precision thin-gauge metal parts.
Waterjet Cutting Application
Thick Metal Sheet Cutting
Water jet cutting technology is very suitable for processing thick steel sheets, aluminum sheets, stainless steel sheets, titanium alloy plates and other materials. This is because, in thick-plate processing, waterjet cutting can minimize issues such as thermal deformation, work hardening, and the heat-affected zone.
Aerospace
In the aerospace industry, titanium alloys, aluminum alloys, nickel-based alloys, and composite materials are all commonly used. Waterjet cutting is a cold-cutting process that minimizes thermal damage to materials, making it well-suited for the aerospace industry.
Medical Industry
Waterjet cutting process can be used for machining certain medical device materials, titanium alloy components, stainless steel parts, and high-performance plastics.
Laser Cutting vs. Waterjet Cutting: Selection Guide
Alright, after conducting an in-depth comparative discussion of these two processes, I believe you now have a relatively clear understanding. Next, I will summarize a set of principles and regulations based on my practical experience, hoping to provide you with some references when choosing a process.
1. When your project meets the following conditions, laser cutting can be prioritized:
- The material is thin sheet metal
- The part has a complex contour
- High cutting speed is required
- A narrow kerf is required
- Mass production with high efficiency requirements
- Minimal heat affect is acceptable
- Subsequent processes include bending, welding, painting, and electroplating
- The parts are primarily sheet metal structural components, enclosures, panels, and brackets
It can be said that, for most thin-gauge metal parts, laser cutting is generally the more efficient option.
2. When your project meets the following conditions, waterjet cutting can be prioritized:
- The material is relatively thick
- The material is sensitive to heat
- Heat-affected zones are unacceptable
- Need to cut composite materials, glass, ceramics, stone, etc.
- Materials are expensive and need to reduce the risk of thermal damage
- Parts have high requirements for material properties in subsequent processes
- You do not want burned edges, oxidized edges, or hardened layers
- Need to process multiple different types of materials
When the material of the part is thicker, heat-sensitive, or the heat-affected zone is not allowed, water jet cutting is usually more suitable.
Selection Decision Table
Finally, here’s a decision-making chart for you.
| Considerations | Laser Cutting Is Better | Waterjet Cutting Is Better |
| Material Type | Thin metal sheets, stainless steel, carbon steel, aluminum | Thick sheets, glass, ceramics, stone, composite materials |
| Material Thickness | Thin sheets and medium-thickness plates | Thick and extra-thick materials |
| Cutting Speed | Fast cutting speed for thin sheets | Slower |
| Heat-Affected Zone | Has heat affected zone | Almost no heat-affected zone |
| Edge Condition | May have issues with oxidation, slag, or thermal discoloration | No burnt edges, no thermal discoloration |
| Fine Features | Components with small holes, narrow slots, and complex contours | Components with complex contours |
| Material Compatibility | Has certain material limitations | A wider range of applicable materials |
| Mass Production | Mass production of thin sheets | Small batches, multiple materials, and thick materials |
Conclusion
That’s all the comparison content above. I believe you now know which process is best suited for your project. Of course, as a professional manufacturer, DSR is also capable of providing high-quality laser cutting services and more. If you have any sheet metal cutting needs, please feel free to contact us. We’ll provide you with an excellent one-stop solution to address your immediate needs.
FAQ
Q1: What are the disadvantages of laser cutting?
A: Equipment and maintenance costs are high, materials and thickness are limited, heat-affected zone.
Q2: What are the disadvantages of waterjet cutting?
A: The cutting speed is relatively slow, operating and maintenance costs are high, it generates a large amount of wastewater and abrasive residue, and waterjet cutting is quite noisy.
Q3: How small of a hole can a waterjet cut?
A: The minimum hole diameter that can be cut by a conventional abrasive waterjet is approximately 0.8–1.5 mm.
Q4: How much does waterjet cutting cost per hour?
A: Generally, the cost of standard waterjet cutting services is approximately $50–150 per hour, while high-precision or large five-axis waterjets can reach over $150–300 per hour.
Q5: How much does waterjet cutting cost per hour?
A: Highly reflective materials such as copper and brass; transparent materials such as ordinary glass; and chlorinated plastics such as PVC and vinyl materials. In addition, excessively thick metal sheets, flammable materials, and heat-sensitive materials are also unsuitable.
Q6: How thick steel can a waterjet cut?
A: Conventional abrasive waterjets can typically cut steel plates 50–150 mm thick, and some high-power waterjets can even cut steel 200–300 mm thick or thicker.
Q7: How long does a waterjet nozzle last?
A: The service life of a gemstone nozzle is approximately 40–120 hours, while that of an abrasive nozzle or mixed-sand nozzle is typically around 60–150 hours. As for high-quality tungsten carbide or composite material nozzles, they can last over 200 hours.
Q8: Why can’t PVC be laser cut?
A: This is because PVC contains chlorine. When this material is exposed to the high temperatures generated by a laser, it releases hydrogen chloride gas and other toxic, corrosive fumes. These gases can be harmful to human health.
Q9: Is a waterjet more accurate than a laser?
A: Laser cutting vs waterjet accuracy is certainly a topic many of you are very concerned about. In fact, laser cutting is generally more precise than waterjet cutting, especially on materials such as thin metal sheets, plastics, and wood. Laser cutting produces narrower kerfs and offers higher positioning accuracy.
Q10: What is the thickest material a laser cutter can cut?
A: Industrial fiber lasers can cut carbon steel that is approximately 20–40 mm thick. For stainless steel, the thickness ranges from approximately 10–30 mm, and for aluminum, from approximately 10–25 mm.
