Corte de Espuma PMI com Laço de Fio de Diamante: 0.8 Teste de Corte de Precisão em mm

Abstrair: Este relatório de aplicação documenta um teste de fatiamento recto de precisão em PMI
(polimetacrilimida) espuma estrutural fornecida por um cliente europeu. Four slices measuring 400 mm x 400 mm x
0.8 mm were produced on an ESH600-4T horizontal Loop de fio de diamante cutting machine
using dry cutting and a fully coated diamond wire. Measured results: variação total de espessura (TTV)
0.013-0.050 milímetros (média 0.036 milímetros), tolerância de espessura +/-0.043 milímetros, surface roughness Ra 0.68-0.82 μm, and maximum
lasca nas bordas 5.5-7.1 μm. Matching machine structure, cutting method and process parameters to the cellular
structure of PMI foam kept material removal stable and held slice dimensional accuracy and cut-surface quality
within a workable range.

Sample test for European customer I | Diamond wire loop cutting process

Overview of the PMI Foam Slicing Test

This test was carried out on PMI foam supplied by a European customer (customer I), with high-precision
straight slicing as the primary requirement. PMI (polimetacrilimida) foam is a high-performance structural foam
known for low density, a uniform cellular structure, and good specific strength and specific stiffness. Its
porous interior gives it a material-removal behaviour quite different from that of dense materials: the diamond
abrasive grains act continuously on the foam skeleton, and excessive cutting load or poorly matched parameters
readily cause local compression, tearing and an uneven cut face, all of which feed directly into slice thickness
and surface quality. This test therefore matched cutting method, machine configuration, wire and process
parameters to the structural characteristics of PMI foam and to the straight-slicing accuracy requirement, portanto
that material removal stayed stable while slice dimensions and cut-surface quality remained under control.

Because of the demands PMI foam places on cutting stability, dimensional accuracy and cross-section quality,
Ensoll applied a diamond wire solution tailored to foam machining. On the machine side, a dedicated horizontal
máquina de serra de fio diamantado dedicada was used so that the wire runs stably along the horizontal
plane, providing a repeatable cutting path and stable feed for straight slicing. On the consumable side, uma
diamond wire suited to PMI foam keeps the abrasive grains acting on the material surface continuously and evenly,
which sustains stable removal. On the cutting-method side, dry cutting avoids coolant entering the foam cells and
lets chips escape promptly during the cut. On that basis, wire running speed and feed rate were adjusted against
the density, cellular structure and target slice thickness of the material, holding the cutting load in a
suitable band and reducing the local compression and tearing that excessive point loads cause in the foam
structure. Matching machine, fio, cutting method and parameters as one set kept the slicing process stable and
brought slice thickness, dimensional accuracy and surface quality under control, establishing a process basis
for high-precision straight slicing of PMI foam.

1. Test Object: Basic Information

• Material: PMI foam
• Dureza: aproximadamente MH 2
• Workpiece dimensions: 400 mm x 400 mm x 50 milímetros
• Cut dimensions: 400 mm x 400 mm x 0.8 milímetros

2. Machine and Wire Selection

Machine type: ESH600-4T. Because PMI foam is lightweight, porous and easily deformed, e
because the requirement is high-precision straight slicing, Ensoll selected a horizontal diamond wire cutting
machine suited to PMI machining. This keeps the wire running stably and preserves cutting-path accuracy, reduces
the effect of machine vibration and cutting-load fluctuation on machining quality, and limits the local
deformation, edge defects and thickness deviation that uneven loading would otherwise produce, thereby improving
both the dimensional accuracy and the cut-surface quality of PMI slices.

• Coolant type: corte a seco. Because PMI foam is porous, lightweight and prone to absorbing
  liquids, dry cutting prevents coolant from entering the cells or remaining in the material and destabilising
  slice dimensions. It also removes the cleaning and drying steps that follow a wet cut, which helps preserve
  structural integrity and dimensional accuracy.
• Wire type: totalmente revestido. UMA fully coated diamond wire loop
  raises grain bonding strength and distribution stability, sustaining a stable and continuous cutting capability.
  It reduces the cutting fluctuation caused by wire wear and grain pull-out, limits tearing and edge defects, e
  improves the dimensional consistency and surface quality of PMI slices.

3. Método de Corte e Vantagens da Máquina

Horizontal cutting method. A máquina utiliza uma estrutura de corte horizontal com um
movimento unidirecional e rápido Loop de fio de diamante como a ferramenta de corte; o
a peça de trabalho é fixada na mesa de trabalho e cortada por alimentação de precisão. Este layout é compacto com um percurso de movimento claro,
o que ajuda a manter a trajetória do fio estável e reduz a influência das flutuações de carga na espessura da fatia e
qualidade da superfície de corte. Também suporta modos de corte fixo, rotativo e oscilante, para que o modo de corte possa ser ajustado
às propriedades do material e aos requisitos de usinagem, ampliando a adaptabilidade da máquina a diferentes materiais e
condições de processo.

Sistema inteligente de controlo de tensão. Tensionamento por mola combinado com feedback de sensor de força
permite operação com tensão constante ou variável de acordo com o estado de usinagem. Manutenção da tensão do fio
stable during the cut improves wire running stability and reduces trajectory fluctuation and the risk of wire
breakage; tension is automatically reduced in standby and during wire changes, which limits wire fatigue and
pulley wear.

Multi-stage automatic cutting. Espessura de corte, number of cuts, cutting speed and cutting
depth can be preset, and the machine then completes continuous cutting automatically to those parameters,
reducing manual interference in the process. For tasks requiring many slices in succession, this raises cutting
efficiency and batch-to-batch consistency.

Breakpoint resume. If the process is interrupted by a wire break, power loss or similar
fault, the system records the current cutting position and resumes from that point once operation is restored,
with no need to reset the workpiece origin. Isto reduz o erro de usinagem do posicionamento repetido, reduz
perda de material e melhora a eficiência da usinagem contínua.

4. Definições de Parâmetros e Método de Arrefecimento

5. Eficiência de Corte e Resultados

5.1 Dados de teste TTV (milímetros)

TTV (Variação total da espessura) foi medido usando uma grelha de nove pontos, método de espessura de duplo sensor num
palco de ventosa, aplicado às fatias de espuma PMI produzidas pelo corte com fio de diamante. As dimensões da amostra cortada foram
400 mm x 400 mm x 0.8 milímetros, com uma espessura nominal de 0.8 milímetros. Antes da medição, o instrumento foi termicamente
stabilised and calibrated with a standard thickness block to reduce zero drift and systematic error. After
dust-free cleaning, each sample was centred on the vacuum chuck and held by negative pressure so that it stayed
in a stable measuring state, limiting the effect of position shift, local warping and deformation on the
thickness readings. The procedure follows the same nine-point method used in our
PEEK slicing test. Thickness data were then collected in sequence at the preset nine
grid positions, and the difference between the largest and smallest readings across all points was taken as the
TTV of that sample, which is used to evaluate the thickness uniformity and machining consistency of PMI foam
slices.

Evaluation: Four PMI foam slices were tested for thickness uniformity by the nine-point
method. TTV values ranged from 0.013 Para 0.050 mm com uma média de 0.036 milímetros. Sample S04 showed the smallest
variation, at 0.013 milímetros. Overall, the results indicate reasonable slice thickness consistency, although some
scatter remains between samples.

5.2 Thickness Tolerance Data (milímetros)

Thickness tolerance was measured by the same nine-point grid method, com 0.800 mm as the nominal thickness of
the sample. The deviation between the measured thickness at each point and the nominal thickness was calculated,
and the maximum positive deviation, maximum negative deviation and thickness deviation range were collated to
evaluate the dimensional accuracy and overall machining consistency of the PMI foam slices.

Evaluation: With 0.800 mm as the nominal thickness, the average thicknesses of the four PMI
foam slices were 0.808, 0.769, 0.761 e 0.757 milímetros, corresponding to deviations of +0.008, -0.031, -0.039 e
-0.043 milímetros. O desvio positivo máximo foi +0.008 milímetros, the maximum negative deviation -0.043 milímetros, and the
overall thickness tolerance +/-0.043 milímetros. The results show that sample thickness tends toward the negative side,
with the last three samples running somewhat thin; thickness control can be improved further through cutting
parameters and dimensional compensation.

5.3 Dados de Rugosidade de Superfície Ra (μm)

Rugosidade da Superfície (Ra) was measured to ISO 4287 using a stylus profiler. Three representative positions,
centre, mid-left and mid-right, were profiled on the cut face of each PMI foam slice, and Ra was calculated at
each position to evaluate surface quality and machining consistency after diamond wire cutting.

Evaluation: Four PMI foam slices were tested for surface roughness by the three-point
method. Average Ra ranged from 0.68 Para 0.82 μm, with little variation between measuring positions, indicating a
broadly uniform cut surface and a stable wire running and material-removal process.

5.4 Dados de lascamento de borda (μm)

Chipping was measured by optical imaging on a toolmaker’s microscope to quantify edge defects on the PMI foam
slices. Sample edges were cleaned before measurement, and the instrument magnification and measuring scale were
calibrated. Each edge region of the slice was then examined under the microscope, recognisable chips, notches
and local edge damage were located and measured, and the defect size at each measuring point was recorded. O
largest defect on a single slice was taken as the primary evaluation index, giving a combined view of edge
integrity and machining quality after cutting PMI foam.

Evaluation: Four PMI foam slices were inspected for edge defects by the four-point method.
Defect sizes were generally small, with maximum chipping between 5.5 e 7.1 um and little difference between
amostras. The results indicate stable edge material removal during diamond wire cutting and good edge integrity on
the slices.

6. Conclusão

The high-precision slicing of PMI foam in this test produced good results, mainly because the dedicated
cutting machine, the dry cutting method and the process parameters were matched as one set. PMI foam is a
high-performance structural foam with low density, an internal cellular structure and good specific strength and
stiffness, and that cellular structure gives it a load behaviour different from dense materials during diamond
wire cutting. The diamond grains act continuously on the internal skeleton, and when the cutting load is too
high or the parameters are poorly matched, local compression, tearing and an uneven cut face appear and affect
slice thickness and dimensional accuracy. Aiming at the structural properties of PMI foam and the straight
slicing accuracy requirement, this test therefore optimised machine selection, cutting method and process
parameters in a targeted way, controlling dimensional accuracy and cut-surface quality while keeping the cutting
process stable.

First, machine selection. Given the demands PMI foam slicing places on motion stability,
cutting accuracy and machine rigidity, a dedicated horizontal diamond wire loop cutting machine for precision
PMI machining was selected. Horizontal cutting keeps the wire running stably along the horizontal plane, which
helps hold the cutting trajectory and feed motion steady and reduces the effect of machine vibration, motion
error and wire running fluctuation on cut position and dimensional accuracy. Stable feed and motion control also
narrow the variation in cutting load, keeping the relative motion between wire and PMI foam consistent. This
reduces the compression and tearing that uneven local loading causes, improves slice dimensional consistency,
and provides a stable machine basis for high-precision PMI slicing.

Second, cutting method. Given the cellular structure and properties of PMI foam, corte a seco
foi usado. Dry cutting introduces no liquid coolant, so liquid cannot enter the foam cells, and the cleaning and
drying steps that would otherwise affect the material state are avoided. O
fully coated diamond wire loop grinds the material directly and continuously, portanto
removal takes place under relatively stable cutting conditions. Controlling wire
running state and cutting load sensibly reduces the local squeezing and tearing the material experiences during
corte, improving the uniformity of the cut cross-section and edge quality, and keeping the process
consistent.

Third, process parameters. Given the low density, cellular structure and removal behaviour of
PMI foam, wire running speed and feed rate were matched accordingly. Parameters were set to keep the wire running
stably and material removal even, avoiding a feed rate so high that the cutting load rises and the foam skeleton
takes a large local force; wire running speed was controlled so that cutting stayed continuous and stable with
less load fluctuation. Targeted adjustment of the cutting parameters kept material removal comparatively smooth
e, while meeting machining efficiency, improved slice thickness and dimensional consistency and the quality of
the cut surface.

Taken together, the results for slice dimensional accuracy, tolerância de espessura, rugosidade superficial (Ra) e
cut-edge quality show that, through coordinated optimisation of a dedicated horizontal cutting machine, dry
cutting and suitable cutting parameters, diamond wire loop cutting meets the requirements of high-precision
straight slicing for PMI foam. The machined samples performed consistently in dimensional accuracy, slice
thickness consistency and cut-surface quality, which indicates that matching machine structure, cutting method
and process parameters to the structure and cutting behaviour of PMI foam effectively improves material removal
and process stability, and provides a process reference for high-precision straight slicing of PMI foam.

Dados de processo relacionados

A janela de parâmetros validada por trás destes resultados – o que cada configuração faz numa espuma celular e para que lado a mover quando aparece um defeito – é publicada como uma referência autónoma: Parâmetros de corte de espuma PMI. Para uma comparação lado a lado com um termoplástico denso medido com a mesma base, consulte PEEK vs espuma PMI, e para o método de medição da espessura em si, o guia TTV de nove pontos.

Perguntas Frequentes

Pode o corte com fio de diamante cortar a espuma PMI até 0.8 espessura em mm?

sim. Neste teste, quatro 400 mm x 400 fatiar espuma PMI para uma espessura nominal de 0.8 mm em um
ESH600-4T horizontal máquina de serra de fio diamantado dedicada. A variação total medida da espessura
(TTV) variou de 0.013 Para 0.050 mm com uma média de 0.036 milímetros, e a tolerância geral da espessura foi
+/-0.043 milímetros, o que é uma base viável para componentes de espuma de precisão.

Por que foi escolhido o corte a seco para espuma PMI em vez de corte húmido?

A espuma PMI é porosa, leve e propensa a absorver líquidos. Dry cutting prevents coolant from entering
the cells or remaining in the material and destabilising slice dimensions, and it removes the cleaning and
drying steps that follow a wet cut. That helps preserve the structure of the foam and the dimensional accuracy
of the slices.

What surface quality can be expected when cutting PMI foam?

Surface roughness was measured to ISO 4287 with a stylus profiler at three positions per slice. Ra médio
variou de 0.68 Para 0.82 um with little variation between measuring positions, and the maximum edge chipping
measured by optical microscopy was 5.5 Para 7.1 μm, indicating a uniform cut surface with good edge integrity.

Why did the PMI foam slices come out slightly thin?

With 0.800 mm as the nominal thickness, the four slices averaged 0.808, 0.769, 0.761 e 0.757 milímetros, so three of
them ran thin by 0.031 Para 0.043 milímetros. This is a systematic offset rather than random scatter, and it can be
corrected directly through cutting parameters and dimensional compensation on the next run.

Which other materials has Ensoll tested with diamond wire loop cutting?

Ensoll has published comparable process data for other polymers and hard-to-cut materials, including a
PEEK precision slicing test and a guide to the
materials suited to diamond wire loop cutting. For general process questions, consulte
o FAQ sobre tecnologia de corte com fio de diamante em loop.

Conteúdo técnico revisto pela equipa de engenharia da Ensoll – um fabricante de laços de fio de diamante com 10+ anos de experiência em produção.